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Protocol Discriminator

Call Reference

Messages

  Call Establishment Messages

    H 01  ALERT

    H 02  CALL PROCEED

    H 07  CONNECT

    H 0F  CONNECT ACKNOWLEDGE

    H 03  PROGRESS

    H 05  SETUP

    H 0D  SETUP ACKNOWLEDGE

  Call Information Phase Message

    H 26  RESUME

    H 2E  RESUME ACKNOWLEDGE

    H 22  RESUME REJECT

    H 25  SUSPEND

    H 2D  SUSPEND ACKNOWLEDGE

    H 21  SUSPEND REJECT

    H 20  USER INFORMATION

  Call Clearing Messages

    H 45  DISCONNECT

    H 4D  RELEASE

    H 5A  RELEASE COMPLETE

    H 46  RESTART

    H 4E  RESTART ACKNOWLEDGE

  Miscellaneous Messages

    H 60  SEGMENT

    H 79  CONGESTION CONTROL

    H 7B  INFORMATION

    H 62  FACILITY

    H 6E  NOTIFY

    H 7D  STATUS

    H 75  STATUS ENQUIRY

Information Elements

  Single octet Information Element

     Shift                      H 9X

     More data                  H A0

     Sending complete           H A1

     Congestion level           H BX

  Variable Length Information Element

     Segmented message          H 00

     Bearer capability          H 04

     Teleservice type           H 05

     Cause                      H 08

     Call identity              H 10

     Call state                 H 14

     Channel identification     H 18

     Charge advice              H 1A

     Facility                   H 1C

     Progress indicator         H 1E

     NetworkSpecificFacilities  H 20

     Notification indicator     H 27

     Display                    H 28

     Date/Time                  H 29

     Keypad facility            H 2C

     Transit counter            H 31

     Party category             H 32

     Signal                     H 34

     Connected number           H 4C

     Connected subaddress       H 4D

     Calling party number       H 6C

     Calling party subaddress   H 6D

     Called party number        H 70

     Called party subaddress    H 71

     Redirecting number         H 74

     Transit network selection  H 78

     Restart indicator          H 79

     Low layer compability      H 7C

     High layer compability     H 7D

     User-user information      H 7E

     Escape for extension       H 7F

Call States

Timers


Protocol Discriminator

 The purpose of the protocol discriminator is to distinguish messages of this specification from any protocol units with also use services of layer 2, but are coded according to other standards.

 The protocol discriminator is the first part of every message.

 The protocol discriminator is coded according to CCITT Q.931.

  8     7     6     5     4     3     2     1

  ===========================================

  0     0     0     0     1     0     0     0    H 08

  ===========================================

  Q.931 protocol discriminator

Protocol Discriminator

8 7 6 5 4 3 2 1

0 0 0 0 0 0 0 0    User specific protocol

0 0 0 0 0 0 0 1    OSI high layer protocol

0 0 0 0 0 0 1 0    X.244

0 0 0 0 0 0 1 1    System management convergence function

0 0 0 0 0 1 0 0    IA5 characters

0 0 0 0 0 1 1 1    CCITT Recomendation  V.120 rate adaption

0 0 0 0 1 0 0 0    Q.931(I.451) call control messages

0 0 0 1 0 0 0 0

    to             reserved for other network layer 3

                   protocols, including  X.25

0 0 1 1 1 1 1 1

0 1 0 0 0 0 0 0

    to             national use

0 1 0 0 0 1 1 1

0 1 0 0 1 0 0 0

    to             reserved for ETSI use

0 1 0 0 1 1 1 1

0 1 0 1 0 0 0 0

    to             reserved for other network layer 3

                   protocols, including  X.25

1 1 1 1 1 1 1 0

 All other values are reserved.


Call Reference

Cref

The purpose of the call reference is to identify the call or facility registration/cancellation request at the local usernetwork interface to which the particular message applies. The call reference does not have end-to-end significance across ISDNs.

The call reference is the second part of every message.

8     7     6     5     4     3     2     1

===========================================

                       Length of             octet 1

0     0     0     0    call reference

                          value (in octets)

===========================================

flag      Call reference value               octet 2

===========================================

Call reference value                         octet 3

===========================================

NOTE for call reference flag (octet2):

bit

8

=

0   the message is sent from the side that originates the call reference

1   the message is sent to the side that originates the call reference


Alert property of Messages
Alert

ALERT

 This message is sent by the user to the network and by the network to the user, to indicate that called user alerting has been initiated.

Significance:       global

Direction:           both

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Channel identification    both            O NOTE 1.  2-*

Facility                  both            O NOTE 2.  2-131

Progress indicator        both            O NOTE 3.  2-*

Display                   n==>u           O NOTE 4.  2-34

Keypad                    n==>u           O NOTE 5.  2-34

User-user information     both            O NOTE 6.  3-131

Party category            both            O NOTE 7.  3

 NOTE 1     The CHANNEL IDENTIFICATION information elemenet is mandatory if this message is the first message in response to SETUP, unless the user accepts the B-channel indicated in the SETUP message.

 NOTE 2     The FACILITY information element is used for functional operation of supplementary services.

 NOTE 3     The PROGRESS INDICATOR informantion element may be included in the event of interworking. Included in the network-user direction in connection with the provision of in-band information/patterns. Included in the user-network direction in connection with provision of in-band information/patters if ETS 300 102 Annex N is implemented.

 NOTE 4     The DISPLAY infromation element may be included if the network provides information that can be presented to the user.

 NOTE 5     The KEYPAD informantion element is not included in ETS 300 102

 NOTE 6     The USER-USER information element is included in the user-network direction when the called user wants to return information to the calling user, or in the network-user direction if the called user included a User-user information element in the ALERT message.

 NOTE 7     The PARTY CATEGORY informantion element is only used for signalling in the Q-reference point. The IE is used to indicate the category of a party involved in a call.


Resume property of Messages
Resume

Resume

 This message is sent by the user to request the network to resume a suspended call.

request the network to resume a suspended call.

Direction:          user-to-network

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    u->n            M          1

Call reference            u->n            M          2-3

Message type              u->n            M          1

Call identity             u->n            O NOTE 1   1

 NOTE 1   Included when the SUSPEND message used to suspend the call included a Call identity information element.


ResumeAcknowledge property of Messages
Resume Acknowledge

Resume Acknowledge

 This message is sent by th network to indicate completion of a request to resume a suspended call.

Direction:          network-to-user

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    n->u            M          1

Call reference            n->u            M          2-3

Message type              n->u            M          1

Channel identification    n->u            M          3-*

Display                   n==>u           O NOTE 1.  2-34

 NOTE 1   The DISPLAY information element is included if the network provides information that can be presented to the user.


ResumeReject property of Messages
Resume reject

Resume reject

 This message is sent by the network to the user to indicate failure of a request to resume a suspended call.

Direction:          network-to-user

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    n->u            M          1

Call reference            n->u            M          2-3

Message type              n->u            M          1

Cause                     n->u            M          4-32

Display                   n->u            O NOTE 1.  2-34

 NOTE 1   The DISPLAY information element is included if the network provides information that can be presented to the user.


Suspend property of Messages
Suspend

Suspend

 This message is sent by the user to request the network to suspend a call.

Direction:          user-to-network

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    u->n            M          1

Call reference            u->n            M          2-3

Message type              u->n            M          1

Call identity             u->n            O NOTE 1.  2-10

 NOTE 1   Included if the user wants to identify the suspended call explicitly.


SuspendAcknowledge property of Messages
Suspend Acknowledge

Suspend Acknowledge

 This message is sent by the network to the user to indicate completion of a request to suspend a call.

Direction:          network-to-user

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    n->u            M          1

Call reference            n->u            M          2-3

Message type              n->u            M          1

Display                   n->u            O NOTE 1.  2-34

 NOTE 1   The DISPLAY information element is included if the network provides information that can be presented to the user.


SuspendReject property of Messages
Suspend reject

Suspend reject

 This message is sent by the network to the user to indicate failure of a request to suspend a call.

Direction:          network-to-user

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    n->u            M          1

Call reference            n->u            M          2-3

Message type              n->u            M          1

Cause                     n->u            M          4-32

Display                   n->u            O NOTE 1.  2-34

 NOTE 1   The DISPLAY information element is included if the network provides information that can be presented to the user.


CallProceed property of Messages
Call Proceeding

CallProceeding

 This message is sent to indicate that requested call establishment has been initiated, and no more call establishment information will be accepted.

Direction:          both

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Channel identification    both            O NOTE 1.  2-*

Progress indicator        both            O NOTE 2.  2-4

Display                   n==>u           O NOTE 3.  2-34

 NOTE 1   The CHANNEL IDENTIFICATION information element is mandatory if this is the first message in response to a SETUP.

 NOTE 2   The PROGRESS INDICATOR information element is included in the event of interworking. Included in connection with the provision of in-band information/patterns.

 NOTE 3   The DISPLAY information element is included if the network provides information that can be presented to the user.


CongestionControl property of Messages
Congestion Control

CONGESTION CONTROL

This message is sent by the user or the  network to indicate the establishment or termination of flow control on the transmission of USER INFORMATION messages.

Direction:          both

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    n==>u           M          1

Call reference            n==>u           M NOTE 1.  2-3

Message type              n==>u           M          1

Congestion level          n==>u           M          1

Cause                     n==>u           O          2-32

Facility                  both            O NOTE 2.  2-131

Display                   n==>u           O NOTE 3.  2-34

NOTE 1   The CALL REFERENCE value may be sent with the global call reference.

NOTE 2   The FACILITY information element is not included in ETS 300 102.

NOTE 3   The DISPLAY information element is included if the network provides information that can be presented to the user.


Connect property of Messages
Connect

This message is sent by the called user to the network and by the network to the calling user to indicate call acceptance by the called user.

Direction:           both

Significance:        global

INFORMATION ELEMENT       DIRECTION       TYPE       LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Channel identification    both            O NOTE 1.  2-*

Facility                  both            O NOTE 2.  2-131

Progress indicator        both            O NOTE 3.  2-4

Display                   n==>u           O NOTE 4.  2-34

Keypad                    n==>u           O NOTE 5.  2-34

Connected number          both            O NOTE 6.  2-22

DATE/TIME                 both            O NOTE 7.  2-7

Low layer compability     both            O NOTE 8.  2-16

User-user information     both            O NOTE 9.  2-131

Charge advice             n==>u           O NOTE 10. 3-8

Party category            both            O NOTE 11. 3

 NOTE 1    The CHANNEL IDENTIFICATOR information element is mandatory if this is the first message in response to a SETUP.

 NOTE 2    The FACILITY information element may be used for functional operation of supplemantary services.

 NOTE 3    The PROGRESS INDICATOR information element is included in the event of interworking. Included in connection with the provision of in-band information/patterns.

 NOTE 4    The DISPLAY information element is included if the network provides information that can be presented to the user.

 NOTE 5    The KEYPAD information element is not included in ETS 300 102.

 NOTE 6    The CONNECTED NUMBER information element is not included in ETS 300 102.

 NOTE 7    The DATE/TIME information element is included by the network on service requested or as subscription option or as network provider default option.

 NOTE 8    The LOW LAYER COMPABILITY information element is included in the user-network direction when the answering user wants to return low layer compability information to the calling user. Included in the network-user direction if the user awarded the call included the call included a low layer compability information element in the CONNECT message. Optionally included for low layer compability negotiation, but some networks may not transport this information element to the calling user.

 NOTE 9    The USER-USER information element is included in the user-network direction when the answering user wants to return information to the calling user. Included in the network-user direction if the user awarded the call included a User-user information element in the CONNECT message.

 NOTE 10   The CHARGE ADVICE information element is not suported by the telia network.

 NOTE 11   The PARTY CATEGORY information element is only used for signalling in the Q-reference point.


ConnectAcknowledge property of Messages
Connect Acknowledge

This message is sent by the network to called user to indicate that a connection has been established. It may also be sent by the calling user to the network to allow symmetrical call control procedures.

Direction:           both

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Channel identification    both            O NOTE 1.  2-*

Display                   n==>u           O NOTE 2.  2-34

 NOTE 1   The CHANNEL IDENTIFICATION information element is available for use by supplementary services (e.g. call waiting).

 NOTE 2   The DISPLAY information element is included if the network provides information that can be presented to the user.


Disconnect property of Messages
Disconnect

 This message is sent by the user to request the network to clear an end-to-end connection or is sent by network to indicate that the end-to-end connection is cleared.

Direction:           both

Significance:       global

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Cause                     both            M          4-32

Facility                  both            O NOTE 1.  2-131

Progress indicator        both            O NOTE 2.  2-4

Display                   n==>u           O NOTE 3.  2-34

User-user information     both            O NOTE 4.  2-131

Charge advice             n==>u           O NOTE 5.  3-8

NOTE 1    The FACILITY information element may be used for functional operation of supplemantary services.

NOTE 2    The PROGRESS INDICATOR informantion element is included in the network-user direction if the network provides in-band tones. However, the user may include the progress indicator and provide in-band tones. But in this case the network will ignore this information element and will not convey the in-band tones.

NOTE 3   The DISPLAY information element is included if the network provides information that can be presented to the user.

NOTE 4   The USER-USER information element is included when the user initiates clearing and wants to pass user information to the remote user at call clearing time.

NOTE 5   The CHARGE ADVICE information element is not included in application telia.


FacilityM property of Messages
Facility

This message may be sent by either the user or the network to control network facilities.

Direction:           both

Significance:        local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          2

Facility                  both            O          2-131

Display                   n==>u           O NOTE 1.  3-34

Keypad                    u==>n           O NOTE 2.  3-34

NOTE 1   The DISPLAY information element is included if the network provides information regarding a supplementary service.

NOTE 2   The KEYPAD information element is included if the user provides information regarding a supplementary service.


FacilityAcknowledge property of Messages
Facility Acknowledge

This message is sent from the network to user in response to a facility control request.

Direction:           both

Significance:        local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          3

Message type              both            M NOTE 1.  2

Display                   n==>u           O NOTE 2.  2-34

Keypad                    u==>n           O NOTE 3.  2-34

NOTE 1   The FACILITY ACKNOWLEDGE message is not included in ETS 300 102.

NOTE 2   The DISPLAY information element is included if the network provides information regarding a supplementary service.

NOTE 3   The KEYPAD information element is included if the user provides information regarding a supplementary service.


Information property of Messages
Information

This message is sent from the user or the network to provide additional information during overlap mode. It may also be used to provide miscellaneous call-related information for stimulus operation of supplementary services.

Direction:           both

Significance:        local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Sending complete          both            O NOTE 1.  1

Cause                     n==>u           O NOTE 2.  2-32

Display                   n==>u           O NOTE 3.  2-34

Keypad                    both            O NOTE 2&4 2-34

Called party number       both            O          2-23

Charge advice             n==>u           O NOTE 5.  3-8

NOTE 1    The SENDING COMPLETE information element is included if the user optionally indicates completion of overlap sending to the network, or if the network optionally indicates completion of overlap receiving to the user.

NOTE 2    The CAUSE information element is a network option, may be used for stimulus operation of supplementary services.

NOTE 3   The KEYPAD information element is included if the network provides information that can be presented to the user.

NOTE 4   The keypad facility information element may be included to convey extra call establishment information to the network or to convey supplementary service information.

NOTE 5   The CHARGE ADVICE information element is not included i application telia.


Notify property of Messages
Notify

This message is sent either from the user or from the network to indicate information pertaining to a call, such as user suspended.

Direction:           both

Significance:       access

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Notification indicator    both            M          3

Display                   n==>u           O NOTE 1.  2-34

NOTE 1   The DISPLAY information element is included if the network provides information that can be presented to the user.


Progress property of Messages
Progress

This message is sent from the network or from the user to indicate the progress of a call in the event of interworking or in releation with the provision of optional in-band information/patterns.

Direction:           both

Significance:        global

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Cause                     both            O NOTE 1.  2-32

Facility                  both            O NOTE 2.  2-131

Progress indicator        both            M          4

Display                   n==>u           O NOTE 3.  2-34

User-user information     n==>u           O NOTE 4.  2-131

NOTE 1   The CAUSE information element is included by the network to provide additional information concerning the provision of optional in-band information/patterns.

NOTE 2   The FACILITY information element is not included in ETS 300 102.

NOTE 3   The DISPLAY informantion element is included if the network provides information that can be presented to the user.

NOTE 4   The USER-USER information element is included when the progress message is sent by the network to indicate that the network has been cleared by the remote user before it reached the active state, and the remote user wants to pass user information at clearing time.


Release property of Messages
Release

This message is sent, from the user or the network, to indicate that the equipment sending the message has disconnected the channel(if any) and intends to release the channel and the call reference, and that the receiving equipment should release the channel and be prepared to release the call reference after sending RELEASE COMPLETE message. And abort any call in the process of being set up.

Direction:            both

Significance:         local, global

                      (global if used as the first clearing message)

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Cause                     both            O NOTE 1.  2-32

Facility                  both            O NOTE 2.  2-131

Display                   n==>u           O NOTE 3.  2-34

User-user information     both            O NOTE 4.  3-131

Charge advice             n==>u           O NOTE 5.  3-8

NOTE 1   The CAUSE information element is mandatory if RELEASE is the first call clearing message, including when RELEASE is send as a result of an error handling condition.

NOTE 2   The FACILITY information element may be included for functional operation of supplementary service.

NOTE 3   The DISPLAY information element is included if the network provides information that can be presented to the user.

NOTE 4   The USER-USER information element is included when the RELEASE is the first call clearing message, and the user initiates call clearing and wants to pass information to the remote user at call claering time.

NOTE 5   The CHARGE ADVICE information element is not included in application telia.


ReleaseComplete property of Messages
Release Complete

This message is sent by the user or the network, to indicate that the equipment sending the message has released the channel(if any) and call reference, the channel is available for reuse, and the receiving equipment shall release the channel and the call reference.

Direction:            both

Significance:         local, global

                      (global if used as the first clearing message)

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Cause                     both            O NOTE 1.  2-32

Facility                  both            O NOTE 2.  2-131

Display                   n==>u           O NOTE 3.  2-34

User-user information     both            O NOTE 4.  3-131

Charge advice             n==>u           O NOTE 5.  3-8

NOTE 1   The CAUSE information element is mandatory if RELEASE COMPLETE is the first call clearing message, icluded when the RELEASE COMPLETE message is sent as a result of an error handling condition.

NOTE 2   The FACILITY information element may be used for functional operation of supplementary services.

NOTE 3   The DISPLAY information element is included if the network provides information that can be presented to the user.

NOTE 4   The USER-USER information element is included when the RELEASE is the first call clearing message, and the user initiates call clearing and wants to pass information to the remote user at call claering time.

NOTE 5   The CHARGE ADVICE information element is not included in application telia.


Restart property of Messages
Restart

This message is sent from one side of the interface to the other to request the recipient to restart (i e, return to an idle condition) the indicated channel(s) or interface. The REStart message is of local significance.

Direction:           both

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M NOTE 1.  2-3

Message type              both            M          1

Channel identification    both            O NOTE 2.  2-5

Display                   n==>u           O NOTE 3.  2-34

Restart indicator         both            M          3

NOTE 1   The CALL REFERENCE information element is sent with the global call reference.

NOTE 2   The CHANNEL IDENTIFICATION information element is included when it is necessary to indicate the particular channel to be restarted.

NOTE 3   The DISPLAY informantion element is included if the network provides information that can be presented to the user.


RestartAcknowledge property of Messages
Restart Acknowledge

This message is sent to acknowledge the receipt of the RESTart message and to indicate that the requested restart is complete.

Direction:           both

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M NOTE 1.  2-3

Message type              both            M          1

Channel identification    both            O NOTE 2.  2-5

Display                   n==>u           O NOTE 3.  2-34

Restart indicator         both            M          3

NOTE 1   The CALL REFERENCE value is sent with the global call reference.

NOTE 2   The CHANNEL IDENTIFICATION information element is included when it is necessary to indicate the particular channel to be restarted.

NOTE 3   The DISPLAY information element is included if the network provides information that can be presented to the user.


Segment property of Messages
Segment

The purpose of the SEGMENT message is if the layer 3 message exceeds N201 (260 octets), the message can be partitioned into several segments.

Direction:           both

Significance:       global

INFORMATION ELEMENT       DIRECTION      TYPE     LENGTH

Protocol discriminator    both            M       1

Call reference            both            M       2-3

Message type              both            M       1

Segmented message         both            M       4

Segmented IE'             both            O       2-->

                                                  etc

'Segmented IE'

The 'Segmented IE' is coded exactly as in the message that is segmentated. The number of 'segmented IE' in the SEGMENT message is depending of the message being segmented, the total length of each SEGMENT message should not exceed N201 octets (260 octets). The SEGMENT message can be repeated maximum 8 times during the segmentation until the whole message is transfered.


MessageType property of Messages
EURO-ISDN Help

Protocol Discriminator

Call Reference

Messages

  Call Establishment Messages

    H 01  ALERT

    H 02  CALL PROCEED

    H 07  CONNECT

    H 0F  CONNECT ACKNOWLEDGE

    H 03  PROGRESS

    H 05  SETUP

    H 0D  SETUP ACKNOWLEDGE

  Call Information Phase Message

    H 26  RESUME

    H 2E  RESUME ACKNOWLEDGE

    H 22  RESUME REJECT

    H 25  SUSPEND

    H 2D  SUSPEND ACKNOWLEDGE

    H 21  SUSPEND REJECT

    H 20  USER INFORMATION

  Call Clearing Messages

    H 45  DISCONNECT

    H 4D  RELEASE

    H 5A  RELEASE COMPLETE

    H 46  RESTART

    H 4E  RESTART ACKNOWLEDGE

  Miscellaneous Messages

    H 60  SEGMENT

    H 79  CONGESTION CONTROL

    H 7B  INFORMATION

    H 62  FACILITY

    H 6E  NOTIFY

    H 7D  STATUS

    H 75  STATUS ENQUIRY

Information Elements

  Single octet Information Element

     Shift                      H 9X

     More data                  H A0

     Sending complete           H A1

     Congestion level           H BX

  Variable Length Information Element

     Segmented message          H 00

     Bearer capability          H 04

     Teleservice type           H 05

     Cause                      H 08

     Call identity              H 10

     Call state                 H 14

     Channel identification     H 18

     Charge advice              H 1A

     Facility                   H 1C

     Progress indicator         H 1E

     NetworkSpecificFacilities  H 20

     Notification indicator     H 27

     Display                    H 28

     Date/Time                  H 29

     Keypad facility            H 2C

     Transit counter            H 31

     Party category             H 32

     Signal                     H 34

     Connected number           H 4C

     Connected subaddress       H 4D

     Calling party number       H 6C

     Calling party subaddress   H 6D

     Called party number        H 70

     Called party subaddress    H 71

     Redirecting number         H 74

     Transit network selection  H 78

     Restart indicator          H 79

     Low layer compability      H 7C

     High layer compability     H 7D

     User-user information      H 7E

     Escape for extension       H 7F

Call States

Timers


Setup

This message is sent by the calling user to the network or by the network to the called user to initiate call establishment.

Direction:           both

Significance:       global

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Sending complete          both            O NOTE 1.  1

Bearer capability         both            M          4-13

Channel identification    both            O NOTE 2.  2-*

Facility                  both            O NOTE 3.  2-131

Progress indicator        both            O NOTE 4.  2-4

NetworkSpecificFacilities both            O NOTE 5.  2-*

Display                   n==>u           O NOTE 6.  2-34

Keypad facility           both            O NOTE 7.  2-34

Calling party number      both            O NOTE 8.  2-24

Calling party subaddress  both            O NOTE 9.  2-23

Called party number       both            O NOTE 10. 2-23

Called party subaddress   both            O NOTE 11. 2-23

Transit network selection u==>n           O NOTE 12. 2-*

Low layer compability     both            O NOTE 13. 2-16

High layer compability    both            O NOTE 14. 2-4

User-user information     both            O NOTE 15. 2-131

Teleservice type          both            O NOTE 16. 2-4

Charge advice             u==>n           O NOTE 17. 4

Transit counter           both            O NOTE 18. 3

Party category            both            O NOTE 19. 3

NOTE 1   The SENDING COMPLETE information element may be included if the user or the network optionally indicates that all information necessary for call establishment is included in the SETUP message.

NOTE 2   The CHANNEL IDENTIFICATION information element is mandatory in the network-user direction. Included in the user-network directionwhen the user wants to indicate a channel. If not included, its absence is interpreated as any channel acceptable.

NOTE 3   The FACILITY information element may be included and is used for functional operation of supplementary services.

NOTE 4   The PROGRESS indicator information element may be included in the event of interworking i.e.the call originated from non ISDN terminal or non-ISDN external line.

NOTE 5   The NETWORK SPECIFIC FACILITIES information element may be included by the calling user or the network to indicate network specific facilities information.

NOTE 6   The DISPLAY information element may be included if the network provides information that can be presented to the user.

NOTE 7   The KEYPAD facility information element may be included to convey extra call establishment information to the network or to convey supplementary service information.

NOTE 8   The CALLING PARTY NUMBER information element may be included by the user or network to indicate to the calling user.

NOTE 9   The CALLING PARTY SUBADDRESS information element is included in user-network direction when the calling user wants to indicate the calling party subaddress. Included in the network-user direction if included by calling user.

NOTE 10  The CALLED PARTY NUMBER information element is included by the user to convey called party number information to the network. The called party number information element is included by the network when called party number information is conveyed to the user.

NOTE 11  The CALLED PARTY SUBADDRESS informaton element is included in the user-network direction when the calling user wants to indicate the called party subaddress. Included in the network-user direction if the calling user included a called party subaddress information element in the SETUP message.

NOTE 12  The TRANSIT NETWORK SELECTION information element is included by the calling user to select a particular transit network.

NOTE 13  The LOW LAYER COMPABILITY information element is included when end-to-end compatibility checking of the low layers is required or when the user requests a bearer service from the network.

NOTE 14  The HIGH LAYER COMPABILITY information element is included when end-to-end compatibility checking of the high layers is required or when the user requests a bearer service from the network.

NOTE 15  The USER-USER INFORMATION element is included in the user-to-network direction if the calling user wishes to transfer user information to the called user. Included in the network-to-user direction if the calling user had included it in the SETUP message.

NOTE 16  The TELESERVICE TYPE information element is included by the user requesting a network provided Teleservice.

NOTE 17  The CHARGE ADVICE information element is not supported in application telia.

NOTE 18  The TRANSIT COUNTER information element is used to limit the number of transit points, in order to protect the network against indefinite looping. This information element is only used for signalling in the Q-reference point.

NOTE 19 The PARTY CATEGORY information element is used to indicate the category of a party involved in a call. This information element is only used for signalling in the Q-reference point.


SetupAcknowledge property of Messages
Setup Acknowledge

This message is sent by the network to the originating calling user or by the called user to the network to indicate call establishment has been initiated, but additional information may be required.

Direction:           both

Significance:       local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Channel identification    both            O NOTE 1.  2-*

Facility                  both            O NOTE 2.  2-131

Progress indicator        both            O NOTE 3.  2-4

Display                   n==>u           O NOTE 4.  2-34

NOTE 1   The CHANNEL IDENTIFICATION information element is mandatory in all cases, exept when the user accepts the specific B-channel indicated in SETUP message.

NOTE 2   The FACILITY information element may be included and is used for functional operation of supplementary services.

NOTE 3   The PROGRESS INDICATOR information element is included in the event of interworking  or in connection with the provision of in-band information/patterns.

NOTE 4   The DISPLAY information element may be included if the network provides information that can be presented to the user.


Status property of Messages
Status

This message is send by the user or network in response to STAUS ENQUIRY message or at any time during a call to report protocol error condition.

Direction:           both

Significance:        local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Cause                     both            M          4-32

Call state                both            M          3

Display                   n==>u           O  NOTE 1. 2-34

NOTE 1    The DISPLAY information element is included if the network provides information that can be presented to the user.


StatusEnquiry property of Messages
Status Enquiry

The STATUS ENQUIRY message may be sent from either the user or the network at any time to solicit a STATUS message.

Direction:           both

Significance:        local

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

Display                   n==>u           O  NOTE 1. 2-34

NOTE 1  The DISPLAY information element is included if the network provides information that can be presented to the user.


UserInformation property of Messages
User Information

This message is sent by the user to the network to transfer information to the remote user.

Direction:           both

Significance:        access

INFORMATION ELEMENT       DIRECTION      TYPE        LENGTH

Protocol discriminator    both            M          1

Call reference            both            M          2-3

Message type              both            M          1

More data                 both            O  NOTE 1. 1

User-user information     both            M          4-131

NOTE 1  The MORE DATA information element is included by the sending user to indicate that another USER information element containing user information pertaining to the same block will follow.


InformationElements property of Messages
Information Element

CCITT INFORMATION ELEMENTS

The information elements listed in this section are CCITT information elements and belong to various codesets

                             8  7  6  5  4  3  2  1

                             ======================

Single octet Information     1  :  :  :  -  -  -  -

Element

Shift                     H 9x  0  0  1  -  -  -  -

More data                 H A0  0  1  0  0  0  0  0

Sending complete          H A1  0  1  0  0  0  0  1

Congestion level          H Bx  0  1  1  -  -  -  -

Variable Length Information  0  :  :  :  -  -  -  -

Element

Segmented message         H 00  0  0  0  0  0  0  0

Bearer capability         H 04  0  0  0  0  1  0  0

Teleservice type          H 05  0  0  0  0  1  0  1

Cause                     H 08  0  0  0  1  0  0  0

Call state                H 14  0  0  1  0  1  0  0

Channel identification    H 18  0  0  1  1  0  0  0

Charge advice             H 1A  0  0  1  1  0  1  0

Facility                  H 1C  0  0  1  1  1  0  0

Progress indicator        H 1E  0  0  1  1  1  1  0

NetworkSpecificFacilities H 20  0  1  0  0  0  0  0

Notification indicator    H 27  0  1  0  0  1  1  1

Display                   H 28  0  1  0  1  0  0  0

Date/Time                 H 29  0  1  0  1  0  0  1

Keypad facility           H 2C  0  1  0  1  1  0  0

Transit counter           H 31  0  1  1  0  0  0  1

Party category            H 32  0  1  1  0  0  1  0

Signal                    H 34  0  1  1  0  1  0  0

Connected number          H 4C  1  0  0  1  1  0  0

Connected subaddress      H 4D  1  0  0  1  1  0  1

Calling party number      H 6C  1  1  0  1  1  0  0

Calling party subaddress  H 6D  1  1  0  1  1  0  1

Called party number       H 70  1  1  1  0  0  0  0

Called party subaddress   H 71  1  1  1  0  0  0  1

Redirecting number        H 74  1  1  1  0  1  0  0

OriginallyCalledPtyNumber H 77  1  1  1  0  1  1  1

Transit network selection H 78  1  1  1  1  0  0  0 codeset 0

Redirection subaddress    H 78  1  1  1  1  0  0  0 codeset 5

Restart indicator         H 79  1  1  1  1  0  0  1 codeset 0

Redirecting subaddress    H 79  1  1  1  1  0  0  1 codeset 5

OriginallyCalledPtySubaddrH 7A  1  1  1  1  0  1  0

Low layer compability     H 7C  1  1  1  1  1  0  0

High layer compability    H 7D  1  1  1  1  1  0  1

User-user information     H 7E  1  1  1  1  1  1  0

Escape for extension      H 7F  1  1  1  1  1  1  1


BearerCapability property of Messages
Bearer Capability

Bearer Capability

The purpose of the bearer capability information element is to indicate a requested bearer service to be provided by the network. And compability check for the called user.

8     7     6     5     4     3     2     1           octet

===========================================

0     0     0     0     0     1     0     0   H 04    1

===========================================

Length of the Bearer Capability contents              2

===========================================

1     Coding      Information transfer

ext   standard    capability                          3

===========================================

0/1   Transfer    Information transfer rate

ext   mode                                            4

===========================================

0/1        Structure    Configura-  Establish-        4a

ext                          tion        ment              NOTE 1

===========================================

 1   Symmetry    Information transfer rate            4b

ext               (destination ==> origination)            NOTE 1

===========================================

0/1   0     1     Layer 1 protocol                    5

ext   L1 ident.   Identification

===========================================

0/1   Synch Nego-    User rate                        5.a

ext  Asynch ti.                                       NOTE 4

===========================================

0/1   Inter-     NIC  NIC  Flow  Flow Spare           5.b

ext   mediate    on   on   contr contr                NOTE 2

      rate       Tx   Rx   on Tx on Rx

===========================================

0/1   Hdr/ Multi Mode LLI  Assig- Inband Spare        5.b

ext   no   frame      nego nor/As-Outband             NOTE 3

      Hdr  supp.           signee negot.

===========================================

0/1   Number of   Number of         Parity            5.c

ext   stop bits   data bits                           NOTE 4

===========================================

1     duplex      modem type                          5.d

ext   mode                                            NOTE 4

===========================================

1     1     0     Layer 2 protocol                    6

ext   L2 ident.   Identification                      NOTE 3

===========================================

1     1     1     Layer 3 protocol                    7

ext   L3 ident.   Identification                      NOTE 3

NOTE 1

If default values are used for all fields of octets 4a and 4b, then these octets shall not be included. If default values are used for all fields of octet 4b, but not for one or more fields of octet 4a, then only octet 4a shall be included. Otherwise, both octets 4a and 4b shall be included.

NOTE 2

This octet may be present only if octet 5 indicates CCITT standardized rate adaptation V.110/X.30.

NOTE 3

This octet may be present only if octet 5 indicates CCITT standardized rate adaptation V.120.

NOTE 4

This octet may be present only if octet 5 indicates either of the CCITT standardized rate adaptation v.110/X.30 or v.120.

Coding Standard (octet 3)

Bits

7 6

===

0 0   CCITT standardized

0 1   reseved for other international standard

1 0   national standard

1 1   standard defined for the network.

Information Transfer Capability (octet 3)

Bits

5 4 3 2 1

=========

0 0 0 0 0            speech

0 1 0 0 0            unrestricted digital information

0 1 0 0 1            restricted digital information

1 0 0 0 0            3.1 kHz audio

1 0 0 0 1            7 kHz audio

1 1 0 0 0            Video

All other values are reserved.

Transfer Mode (octet 4)

Bits

7 6

===

0 0                  Circuit mode

1 0                  packet mode

Information Transfer Rate (octets 4 and 4b,bit 5 to 1)

Bits

5 4 3 2 1            Circuit mode      Packet mode

=========

0 0 0 0 0                -             This code is for packet mode calls

1 0 0 0 0            64 kbit/s              -

1 0 0 0 1            2X64 kbit/s            -

1 0 0 1 1            384 kbit/s             -

1 0 1 0 1            1536 kbit/s            -

1 0 1 1 1            1920 kbit/s            -

NOTE 1

When the information transfer rate 2X64 kbit/s is used the coding of octet 3 and 4 refer to both 64 kbit/s channels.

NOTE 2

When octet 4b is omitted, the bearer capability is bi-directional symmetric at the information transfer rate specified in octet 4.When octet 4b is included, the information transfer rate in octet 4 refers to the origination -> destination direction.

Structure (octet 4a)

Bits

7 6 5

=====

0 0 0                Default

0 0 1                8 kHz integrity

1 0 0                service data unit integrity

1 1 1                unstructured

NOTE

If octet 4a is omitted, or the structure field is coded "000", then the value of the structure attribute is according to the following:

Transfer Mode        Transfer Capability   Structure

===========================================================

Circuit              speech                8 kHz integrity

Circuit              unrestricted digital  8 kHz integrity

Circuit              restricted digital    8 kHz integrity

Circuit              audio                 8 kHz integrity

Circuit              video                 8 kHz integrity

Packet               unrestricted digital  service data unit integrity

Configuration (octet 4a)

Bits

4 3

===

0 0                  point-to-point

All other values are reserved.

NOTE

If octet 4a is omitted, the configuration is assumed to be point-to-point.

Establishment (octet 4a)

Bits

2 1

===

0 0                  demand

All other values are reserved.

NOTE       if octet 4a is omitted then demand is assumed.

Symmetry (octet 4b)

Bits

7 6

===

0 0                  bi-directional symmetric

All other values are reserved.

NOTE       if octet 4b is omitted, bi-directional symmetric is assumed.

User information layer 1 Protocol(octet 5)

Bits

5 4 3 2 1

=========

0 0 0 0 1       CCITT standardized rate adaptation

                V.110/X.30. This implies the presence

                of octet 5a and optionally octet 5b,

                5c and 5d as defined below.

0 0 0 1 0       Recommendation G.711 æ-law.

0 0 0 1 1       Recommendation G.711 A-law.

0 0 1 0 0       Recommendation G.721 32 kbit/s ADPCM and rec. I.460

0 0 1 0 1       Recommendation G.722 and G.725 7 kHz audio.

0 0 1 1 0       Recommendation G.7xx 384 kbit/s video.

0 0 1 1 1       Non-CCITT standardized rate adaptation.

This implies the presence of octet 5a and optionally octets 5b, 5c and 5d. The use of this codepoint indicates that the user rate specified in octet 5a is defined in accordance with the non-CCITT standardized rate adaptation scheme. Additionally, octets 5b, 5c and 5d, if present, are defined consistent with the specified rate adaptation.

0 1 0 0 0       CCITT standardized rate adaptation

V.120. This implies the presence of octet 5a and 5b and optionally octet 5c and 5d as defined below.

0 1 0 0 1       CCITT standardized rate adaptation

                    X.31 HDLC flag stuffing.

All other values are reserved.

Synchronous/asynchronous (octet 5a)

Bit

7

=

0                    synchronous

1                    asynchronous

Negotiation (octet 5a)

Bit

6

=

0                    in-band negotiation not possible

1                    in-band negotiation possible

User Rate (octet 5a)

Bits

5 4 3 2 1

=========

0 0 0 0 0            rate is indicated by E-bits, spec. I.460

0 0 0 0 1            0.6 kbit/s Recommendation V.6 and X.1

0 0 0 1 0            1.2 kbit/s Recommendation V.6

0 0 0 1 1            2.4 kbit/s Recommendation V.6 and X.1

0 0 1 0 0            3.6 kbit/s Recommendation V.6

0 0 1 0 1            4.8 kbit/s Recommendation V.6 and X.1

0 0 1 1 0            7.2 kbit/s Recommendation V.6

0 0 1 1 1            8   kbit/s Recommendation I.460

0 1 0 0 0            9.6 kbit/s Recommendation V.6 and X.1

0 1 0 0 1            14.4 kbit/s Recommendation V.6

0 1 0 1 0            16 kbit/s Recommendation I.460

0 1 0 1 1            19.2 kbit/s Recommendation V.6

0 1 1 0 0            32 kbit/s Recommendation I.460

0 1 1 1 0            48 kbit/s Recommendation V.6 and X.1

0 1 1 1 1            56 kbit/s Recommendation V.6

1 0 0 0 0            64 kbit/s Recommendation X.1

1 0 1 0 1            0.1345 kbit/s Recommendation X.1

1 0 1 1 0            0.100 kbit/s Recommendation X.1

1 0 1 1 1            0.075/1.200 kbit/s Recommendation V.6 and X.1

1 1 0 0 0            1.200/0.075 kbit/s Recommendation V.6 and X.1

1 1 0 0 1            0.050 kbit/s Recommendation V.6 and X.1

1 1 0 1 0            0.075 kbit/s Recommendation V.6 and X.1

1 1 0 1 1            0.110 kbit/s Recommendation V.6 and X.1

1 1 1 0 0            0.150 kbit/s Recommendation V.6 and X.1

1 1 1 0 1            0.200 kbit/s Recommendation V.6 and X.1

1 1 1 1 0            0.300 kbit/s Recommendation V.6 and X.1

1 1 1 1 1            12 kbit/s Recommendation V.6

*octet 5b for V.110/X.30 rate adaptation*

Intermediate rate (octet 5b)

Bits

7 6

===

0 0             not used

0 1             8 kbit/s

1 0             16 kbit/s

1 1             32 kbit/s

Network Independent Clock (NIC) on Transmission (TX) (octet 5b)

Bit

5

=

0               not require to send data with Network Independed Clock

1               requires to send data with Network Independed Clock

Network Independent Clock (NIC) on Reception (Rx) (octet 5b)

Bits

4

=

0               cannot accept data with NIC

1               can accept data with NIC

Flow control on Transmission (Tx) (octet 5b)

Bit

3

=

0               not required to send data with flow control mechanism

1               required to send data with flow control mechanism

Flow control on Reception (Rx) (octet 5b)

Bit

2

=

0               cannot accept data with flow control

                mechanism (i.e. sender does not support

                this optional procedure).

1               can accept data with flow control

                mechanism (i.e. sender does support this

                optional procedure).

*octet 5b for V.120 rate adaptation*

Rate adaptation header/not header (octet 5b)

Bit

7

=

0               rate adaptation header not included

1               rate adaptation header included

Multiple frame established support in Data link (octet 5b)

Bit

6

=

0               multiple frame establishment not

                supported, only UI-frames allowed.

1               multiple frame establishment supported.

Mode of operation (octet 5b)

Bit

5

=

0               bit transparent mode of operation

1               protocol sensitive mode of operation

Logical link identifier negotiation (octet 5b)

Bit

4

=

0               default, LLI = 256 only

1               full protocol negotiation

Assignor/assignee (octet 5b)

Bit

3

=

0               message originator is "Default assignee"

1               message originator is "Assignor only"

In-band/outband negotiation (octet 5b)

Bit

2

=

0               negotiation is done with USER INFORMATION

                messages on a temporary signalling

                connection

1               negotiation is done in-band using

                logical link zero.

Number of stop bits (octet 5c)

Bits

7 6

===

0 0                  not used

0 1                  1 bit

1 0                  1.5 bits

1 1                  2 bits

Number of data bits excluding parity bit if present (octet 5c)

Bits

===

0 0                  not used

0 1                  5 bits

1 0                  7 bits

1 1                  8 bits

Parity information (octet 5c)

Bits

3 2 1

=====

0 0 0                odd

0 1 0                even

0 1 1                none

1 0 0                forced to 0

1 0 1                forced to 1

Duplex mode (octet 5d)

Bit

7

=

0                   half duplex

1                   full duplex

Modem Type (octet 5d)

Bits

6 5 4 3 2 1

===========

0 0 0 0 0 0      Reserved

0 0 0 0 0 1      V.21

0 0 0 0 1 0      V.22

0 0 0 0 1 1      V.22 bis

0 0 0 1 0 0      V.23

0 0 0 1 0 1      V.26

0 0 0 1 1 0      V.26 bis

0 0 0 1 1 1      V.26 ter

0 0 1 0 0 0      V.27

0 0 1 0 0 1      V.27 bis

0 0 1 0 1 0      V.27 ter

0 0 1 0 1 1      V.29

0 0 1 1 0 0      V.32

0 0 1 1 0 1      V.35

1 0 0 0 0 0

    to           Reserved for national use

1 1 1 1 1 1

User information layer 2 protocol (octet 6)

Bits

5 4 3 2 1

=========

0 0 0 1 0            CCITT Recommendation Q.921 (I.441)

0 0 1 1 0            CCITT Recommendation X.25 link level

All other values are reserved

User information layer 3 protocol (octet 7)

Bits

5 4 3 2 1

=========

0 0 0 1 0            CCITT Recommendation Q.931 (I.451)

0 0 1 1 0            CCITT Recommendation X.25, packet layer

All other values are reserved


Call Identity

Call State

The purpose of the call identity information element is to identify the suspended call.

8    7    6    5    4    3    2    1                  octet

====================================

0    0    0    1    0    0    0    0       H 10       1

====================================

     Length of call identity                          2

====================================

Call identity (any bit pattern                        3

allowed, e.g. IA5 characters)

====================================


CallState property of Messages
Call State

Call State

The purpose of the call state information element is to describe the current status of a call or a global interface state.

8    7    6    5    4    3    2    1                  octet

====================================

0    0    0    1    0    1    0    0       H 14       1

====================================

     Length of call state contents                    2

====================================

Coding    Call state / Global interface               3

standard  value        state value

====================================

Coding standard (octet 3)

Bits

8 7

===

0 0        CCITT standardized coding

0 1        reserved for international standards

1 0        national standard

1 1        standard defined for the network

           present on the network side of

           the interface

Call state value (octet 3)

State    User state                 Network state

Value

=========================================================

0        U0     Null                N0      Null

1        U1     Call Initiated      N1      Call Initiated

2        U2     Overlap sending     N2      Overlap sending

3        U3     Outgoing call       N3      Outgoing call

                proceeding                  proceeding

4        U4     Call Delivered      N4      Call Delivered

6        U6     Call Present        N6      Call Present

7        U7     Call Received       N7      Call Received

8        U8     Connect Request     N8      Connect Request

9        U9     Incoming call       N9      Incomming call

                proceeding                  proceeding

10       U10    Active              N10     Active

11       U11    Disconnect request  N11     Disconnect request

12       U12    Disconnect          N12     Disconnect indication

                indication

15       U15    Suspend request     N15     Suspend request

17       U17    Resume request      N17     Resume request

19       U19    Release request     N19     Release request

22                                  N22     Call abort

25       U25    Overlap receiving   N25     Overlap receiving

All other values are reserved

Global interface state value (octet 3)

State      State

=======================

0         Rest 0   Null

61        Rest 1   Restart Request

62        Rest 2   Restart


CalledPartyNumber property of Messages
Called Party Number

Called party number

The purpose of the called party number information element is to identify the called party of a call.

8     7     6     5     4     3     2     1           octet

===========================================

0     1     1     1     0     0     0     0    H 70   1

===========================================

   Length of Called Party Number contents             2

===========================================

1         Type of       Numbering plan                3

Ext       number        identification

===========================================

0                    Number digits                    4 etc

Spare                (IA5 characters) NOTE

===========================================

NOTE

The number digits appear in multiple octets  4-*, in the same order in which they would be entered first is located in the first octet 4.

Type of number (octet 3)

Bits

7 6 5

=====

0 0 0       unknown

0 0 1       international number

0 1 0       national number

0 1 1       network specific number

1 0 0       subscriber number

1 1 0       abbreviated number

1 1 1       reserved for extension

Numbering plan identification (octet 3)

Bits

4 3 2 1

=======

0 0 0 0              unknown

0 0 0 1              ISDN/Telephony numbering plan (Rec E.164/E.163)

0 0 1 1              data numbering plan (Rec X.121)

0 1 0 0              telex numbering plan (Rec F.69)

1 0 0 0              national standard numbering plan

1 0 0 1              private numbering plan

1 1 1 1              reserved for extension


CalledPartySubaddress property of Messages
Called Party Subaddress

Called Party Subaddress

The purpose of the called party subaddress information element is to identify the subaddress of the called party. The network does not interpret this information.

8     7     6     5     4     3     2     1           octet

===========================================

0     1     1     1     0     0     0     1   H 71    1

===========================================

 Length of Called Party Subaddress contents           2

===========================================

1         Type of    odd/even 0     0     0           3

Ext       Subaddress ind.     Reserved

===========================================

Subaddress Information (NOTE)                       4 etc

===========================================


CallingPartyNumber property of Messages
Calling Party Number

Calling Party Number

The purpose of the calling party number information element is to identify the origin of a call.

8     7     6     5     4     3     2     1           octet

===========================================

0     1     1     0     1     1     0     0   H 6C    1

===========================================

   Length of Calling Party Number contents            2

===========================================

0/1       Type of         Numbering plan              3

          number          identification

===========================================

1     Present     0     0     0     Screening         3a

Ext   Indicator   Spare Reserved    indicator

===========================================

0                    Number digits                    4

Spare                (IA5 characters)

===========================================

Type of Number (octet 3)

Bits

7 6 5

=====

0 0 0       unknown

0 0 1       international number

0 1 0       national number

0 1 1       network specific number

1 0 0       subscriber number

1 1 0       abbreviated number

1 1 1       reserved for extension

Numbering plan identification (octet 3)

Bits

4 3 2 1

=======

0 0 0 0              unknown

0 0 0 1              ISDN/Telephony numbering plan (Rec E.164/E163)

0 0 1 1              data numbering plan (Rec. X.121)

0 1 0 0              telex numbering plan (Rec. F.69)

1 0 0 0              national standard numbering plan

1 0 0 1              private numbering plan

1 1 1 1              reserved for extension

Presentation indicator (octet 3a)

Bits

7 6

===

0 0       presentation allowed

0 1       presentation restricted

1 0       number not available due to interworking

1 1       reserved

NOTE       If octet 3a is omitted then presentation allowed is assumed.

Screening indicator (octet 3a)

Bits

2 1

===

0 0       user-provided, not screened

0 1       user-provided, verified and passed

0 1       user-provided, verified and failed

1 1       Network provided

Number digits (octets 4, etc)

This field is coded with IA5 characters.


CallingPartySubaddress property of Messages
Calling Party Subaddress

Calling Party Subaddress

The purpose of the calling party subaddress information element is to associated with the origin of the call.

8     7     6     5     4     3     2     1

===========================================

0     1     1     0     1     1     0     1  H 6C octet 1

===========================================

Length of Calling Party Subaddress contents             2

===========================================

1     Type of       odd/even  0     0     0             3

Ext   subaddress    ind.      Reserved

===========================================

       Subaddress Information (NOTE)                    4

===========================================             etc


Cause property of Messages
Cause

Cause

The purpose of the cause information element is to describe the reason for generating certain messages, to provide diagnostic information in the event of procedural errors and to indicate the location of the cause originator.

The cause information element may be repeated in a message e.g. to report multiple errors associated with a single call, but only one cause value is transferred to the remote user through the network.

8     7     6     5     4     3     2     1           octet

===========================================

0     0     0     0     1     0     0     0   H 08    1

===========================================

      Length  of Cause contents                       2

===========================================

0/1   Coding      0          Location                 3

      Standard  Spare

===========================================

1         Recommendation                              3a

Ext

===========================================

1                    Cause value                      4

Ext

===========================================

                     Diagnostics                      5

===========================================

Coding standard (octet 3)

Bits

7 6

===

0 0                  CCITT standard

0 1                  reserved for other international standards

1 0                  national standard

1 1                  standard specific to identified location

Location (octet 3)

Bits

4 3 2 1

=======

0 0 0 0              user

0 0 0 1              private network serving the local user

0 0 1 0              public network serving the local user

0 0 1 1              transit network

0 1 0 0              public network serving the remote user

0 1 0 1              private network serving the remote user

0 1 1 1              international network

1 0 1 0              network beyond an interworking point

Recommendation (octet 3a)

Bits

7 6 5 4 3 2 1

=============

0 0 0 0 0 0 0        Q.931

0 0 0 0 0 1 1        X.21

0 0 0 0 1 0 0        X.25

Cause Value (octet 4)

The cause value is diveded in two fields, a class (bits 5 through 7) and a value within the class (bits 1 through 4).

The class indicates the general nature of the event.

Class values

Bits

7 6 5

=====

0 0 0                normal event

0 0 1                normal event

0 1 0                resources unavailable

0 1 1                service or option not available

1 0 0                service or option not implemented

1 0 1                invalid message

1 1 0                protocol error

1 1 1                interworking

Diagnostic (octet 5)

Diagnostic information is not available for every cause. The inclusion of diagnostic is optional. When available the coding of diagnostic(s) is the same as for the corresponding information element.

Cause information valuse CCITT (octet 4)

Class: normal event

Cause No   Cause                      Diagnostics

==================================================

   1       Unassigned (unallocated)         -

           number

   2       No route to specified            -

           transit network

   3       No route to destination          -

   6       Channel unacceptable             -

  16       Normal clearing                  -

  17       User busy                        -

  18       No user responding               -

  19       No answer from user              -

  21       Call rejected                    -

  22       Number changed                   -

  27       Destination out of service       -

  28       Invalid number format            -

  29       Facility request rejected.  Fac. identifier

  30       Response to STATUS ENQUIRY       -

  31       Normal, unspecified              -

===================================================

Class: resource unavailable

Cause No   Cause                      Diagnostics

==================================================

  34       No circuit/channel available

  38       Network out of order             -

  41       Temporary failure                -

  42       Switching equipment congestion

  43       User information discarded   Discarded infor-

                                        mation element

                                        identifier(s).

  44       Requested circuit/channel not available

  47       Resource unavailable, unspecified

==================================================

Class: service or option not available

Cause No   Cause                      Diagnostics

==================================================

  49       Quality of service unavailable

  50       Not subscribed to requested facility.

  57       Bearer capability not authorized

  58       Bearer capability not presently available

  63       Service or option not available, unspecified

==================================================

Class: service or option not implemented

Cause No   Cause                      Diagnostics

==================================================

  65       Bearer capability not implemented

  66       Channel type not implemented

  69       Requested facilty not implemented

  70       Only restricted digital information bearer capability is

           available

  79       Service or option not available, unspecified

==================================================

Class: invalid message

Cause No   Cause                      Diagnostics

==================================================

  81       Invalid call reference value

  82       Identified channel does not exist

  88       Incompatible destination bearer capability

                                        identifier or

                                        Teleservice

                                        identifier or

                                        Low Layer comp.

                                        identifier or

                                        High Layer comp.

                                        identifier

  91       Invalid transit network selection

  95       Invalid message, unspecified   -

=================================================

Class: protocol error

Cause No   Cause                      Diagnostics

==================================================

  96       Mandatory information        Information

           element is missing           element

                                        identifier(s)

  97       Message type non-existing    Message type

           or not implemented

  98       Message not compatible       Message type

           with call state or message

           type non-existing or

           not implemented

  99       Information element non-    Information

           existing or not implemented element

                                       identifier(s)

  100      Invalid information         Information

           element contents            element

                                       identifier(s)

  101      Message not compatible      Message type

           with call state

  102      Recovery on timer expiry    Time number NOTE 1

  111      Protocol error, unspecified    -

==================================================

Class: interworking

Cause No   Cause                      Diagnostics

==================================================

  127      Interworking unspecified       -

NOTE 1

The timer number is coded in IA5 characters e.g timer T308 is coded, '33','30' and '38'.


ChannelIdentification property of Messages
Channel Identification

Channel Identification

The purpose of the channel identification information element is to identify a channel within the interface(s) controlled by these signalling procedures.

8      7      6      5      4      3      2      1       octet

==================================================

0      0      0      1      1      0      0      0  H 18   1

==================================================

     Length of Channel Identification contents             2

==================================================

1      Int    Int    0      Pref/  D-ch   Info chnl        3

Ext    id     type   Spare  Excl   ind    selection

==================================================

0/1            Interface identifier                        3.1

Ext

==================================================

1       Coding       Number/       Channel                 3.2

Ext     standard     Map           type                  NOTE 1

==================================================

Channel number/slot map                                    3.3

==================================================       NOTE 2, 3

NOTE 1

When the "interface type" field in octet 3 indicates "basic interface", octets 3.2 and 3.3 are funtionally replaced by the "information channel selection" field in octet 3, and thus omitted.

NOTE 2

When channel number is used, bit 8 is reserved for use as an extension bit.

NOTE 3

When channel number is used, this octet  may be repeated to indicate multiple channels.

Interface identifier present (octet 3)

Bit

7

=

0         interface implicitly identified; NOTE 1

1         interface explicitly identified; Not applicable to ETS 300 102

NOTE 1  The interface which includes the D-channel carrying this information element is indicated.

Interface type (octet 3)

Bit

6

=

0         basic interface

1         primary interface

Preferred/exclusive (octet 3)

Bit

4

=

0         indicated channel is preferred

1         exclusive: only the indicated channel is acceptable

D-channel indicator (octet 3)

Bit

3

=

0         the channel identified is not the D-channel

1         the channel identified is the D-channel

Information channel selection (octet 3)

Bits

2 1    Basic interface     Primary interface

=============================================

0 0     no channel          no channel

0 1     B1 channel          as in following octets

1 0     B2 channel          reserved

1 1     any channel         any channel

Coding standard (octet 3.2)

Bits

7 6

===

0 0                  CCITT standard

0 1                  reserved for other international standards

1 0                  national standards

1 1                  other network standard

Number/map (octet 3.2)

Bit

5

=

0                    channel is indicated by the number

                     in the following octet.

1                    channel is indicated by the slot

                     map in the following octet(s).

Channel type/map element type (octet 3.2)

Bits

4 3 2 1

=======

0 0 1 1              B-channel units

0 1 1 0              H0-channel units

1 0 0 0              H11-channel units

1 0 0 1              H12-channel units

Channel number (octet 3.3)

Bits

8 7 6 5 4 3 2 1

0 x x x x x x x      binary number assigned to the channel.

                     bit 8 is reserved for extension.


ChargeAdvice property of Messages
Charge Advice

Charge advice

The purpose of the charge advice information element is to convey charging information to the user from the network.

The charge information may be in the form of charging period information or information about the number of charging units.

8     7     6     5     4     3     2     1           octet

===========================================

0     0     0     1     1     0     1     0   H 1A    1

===========================================

    Length of Charge Advice contents                  2

===========================================

0/1  Coding   National/ 0   Type of charging          3

Ext  standard CEPT     Spare

===========================================

0/1       Charging period                             3a

Ext

===========================================

1         Charging period multiplier                  3b

Ext

===========================================

1    Tariff type      Call class  Charging            3c

Ext                               indicator

===========================================

          Number of charging units (NOTE 1)           4

===========================================           4.1

                                                      4.2

NOTE 1

The number of charging units is binary coded. The least significant bit is bit 1 of octet 4 and the most significant bit is bit 8 of octet 4.2 (or 4.1 or 4).

NOTE 2

The presence (and the number of) octet(s) 4 is determined by the length of the charge advice information element content, as this is the last field of the information element.

NOTE 3

octet 3c will only be included if octet 3 bit 5 indicates national standard. If octet 3c is included, octets 3a and 3b will not be included.

Coding standard (octet 3)

Bits

7 6

===

1 0                  National standard

1 1                  Standard defined for the network

                     present on the network side of

                     the interface

NOTE

No coding is defined for CCITT

National/CEPT standard (octet 3)

Bits

5

=

0                    National standard

1                    CEPT standard (as described below)

Type of charging (octet 3)

Bits

3 2 1

=====

0 0 0                Free of charge (NOTE 1)

0 0 1                Charge on duration (NOTE 2)

0 1 0                Charge on answer (NOTE 3)

0 1 1                Charge increment (NOTE 4)

1 0 0                (Sub-)total charge (NOTE 5)

1 0 1                Charge meter value (NOTE 6)

NOTE 1

In this case the following octets are omitted

NOTE 2

Rate is indicated in the following octets

NOTE 3

The number of charge units may be indicated in octet 4.

NOTE 4

Number of charge units charged since the previous charging information was sent

NOTE 5

Number of charge units charged for the call at the time this information is sent

NOTE 6

Number of charge units charged for the call at the time this information is sent. octet 3 bit 5-7 must indicate 'National standard'

Charging period (octet 3a)

If octet 3b is not present (bit 8 set to 1) the charging period is indicated in seconds and binary coded in bits 1-7, bit 1 being the least significant.

If octet 3b is present (bit 8 set to 0) the charging period is coded as defined below.

Bits

7  6  5  4  3  2  1

===================

0  0  0  1  0  0  0     0.1 second intervall

0  0  0  1  0  0  1     1.0 second intervall

0  0  0  1  0  1  0    10.0 second intervall

0  0  0  1  0  1  1    60.0 second intervall

Charging period multiplier (octet 3b)

Binary coded in bits 1-7 (bit 1 the least significant)

NOTE

The length of the charging period is obtained by multiplying the charging period multiplier with the charging period value in octet 3a.

Tariff type (octet 3c)

Bits

7 6 5

=====

0 0 0      Implicit (Used for intrasubscriber calls

           i.e. calls within own private network)

0 0 1      Local call

0 1 0      National call

0 1 1      International call

1 0 0      Special services

Call class (octet 3c)

Bits

4 3

===

0 0        Intrasubscriber call i.e. call within own

           private network.

0 1        Switched network (Other type of call)

Charging type (octet 3c)

Bits

2 1

===

0 0        Group

0 1        Individual

Number of charging units (octet 4, 4.1, 4.2)

Binary coded value.


DateTime property of Messages
Date/Time

Date/Time

The purpose of Date/time information element is to provide the date and the time to the user. It indicates a point in time when the message has been generated by the network.

It is network dependent wether the time indicated is local time or Coordinated Universal Time (CUT), and which calender is used for referencing the date.

8     7     6     5     4     3     2     1           octet

===========================================

0     0     1     0     1     0     0     1  H 29     1

===========================================

       Length of Date/Time contents                   2

===========================================

                 Year                                 3

===========================================

                 Month                                4

===========================================

                 Day                                  5

===========================================

                 Hour                                 6

===========================================

                 Minute                               7

===========================================

                 Second                               8

===========================================


CongestionLevel property of Messages
Congestion Level

Congestion Level

The purpose of the congestion level information element is to describe the congestion status of the call. The congestion level information element is a single octet information element.

This information element is used for flow control of USERINFO messages.

8     7     6     5     4     3     2     1

===========================================

1     0     1     1       Congestion level   H Bx   octet 1

===========================================

Congestion level (octet 1)

Bits

4 3 2 1

=======

0 0 0 0              receiver ready

1 1 1 1              receiver not ready


ConnectedNumber property of Messages
Connected Number

Connected Number

The purpose of the connected number information element is to indicate which number is connected to a call. The connected number may be different from the calling party or called party number because of changes (e g call redirection, transfer) during the lifetime of the call.

8     7     6     5     4     3     2     1        octet

===========================================

0     1     0     0     1     1     0     0  H 6C  1

===========================================

     Length of Connected Number contents           2

===========================================

0/1       Type of       Numbering plan             3

          number        identification

===========================================

1     Present     0     0     0    Screening       3a

Ext   indicator  Spare  Reserved   indicator

===========================================

0                    Number digits                 4 etc

Spare                (IA5 characters)

===========================================

NOTE

octets 3, 3a and 4 are coded in the same way as Calling Party Number


ConnectedSubaddress property of Messages
Connected Subaddress

Connected Subaddress

The purpose of the Connected Subaddress information element is to identify the subaddress of one connected party of a call. The connected subaddress may be different from a called party subaddress because of changes during the lifetime of the call.

8     7     6     5     4     3     2     1           octet

===========================================

0     1     0     0     1     1     0     1   H 6D    1

===========================================

  Length of Connected Subaddress contents             2

===========================================

1         Type of    Odd/even 0     0     0           3

Ext       subaddress  ind      Spare

===========================================

        Subaddress information                        4

===========================================


Display property of Messages
Display

Display

The purpose of the display information element is to convey facility control codes. The information contained in this element is coded in IA5 characters.

The maximum length of the Display information element is 34 octets.

8     7     6     5     4     3     2     1           octet

===========================================

0     0     1     0     1     0     0     0   H 28    1

===========================================

          Length of Display contents                  2

===========================================

          Display information                         3

===========================================


EscapeForExtension property of Messages
Escape for extension

Escape for extension

The purpose of escape for extension is invoke signalling between users, not connected to the protocol.

8     7     6     5     4     3     2     1

===========================================

0     1     1     1     1     1     1     1   H 7F octet 1

Escape for extension

===========================================

Length of information element contents (octets)         2

===========================================

1        Information element identifier                 3

===========================================

         Contents of information element                4

===========================================


Facility property of Messages
Facility

Facility

The purpose of the facility information element is to indicate the invocation and operation of supplementary services, identified by the corresponding operation value within the facility information element.

The Facility information element may be repeated in a given message.

8     7     6     5     4     3     2     1           octet

===========================================

0     0     0     1     1     1     0     0  H 1C     1

===========================================

Length of Facility contents                           2

===========================================

1     0     0         protocol profile                3

===========================================

                Component(s)                          4

===========================================

NOTE

One or more components may be included depending on specific service requirements. Multiple components may be sent in one Facility information element or in more than one (individual) Facility information element.

Protocol profile (octet 3)

Bits

5 4 3 2 1

=========

1 0 0 0 1            remote operations protocol

ECMA format

8     7     6     5     4     3     2     1           octet

===========================================

0     0     0     1     1     1     0     0           1

===========================================

       Length of Facility contents                    2

===========================================

1     0     0          Protocol profile               3

===========================================

         Network Facility Extension                   4

===========================================

         Interpretation Apdu

===========================================

         Component Part

===========================================

Protocol profile (octet 3)

Bits

5 4 3 2 1

=========

1 0 0 0 1            supplementary service applications discriminator

The Facility IE content is using ASN.1 and is BER encoded. For coding of the Facility IE, see the appropriate supplementary service specification.


HighLayerCompability property of Messages
High Layer Compability

High Layer Compatibility

The purpose of the high layer compatibility information element is to provide a means which should be used by the remote user for compatibility checking.

8     7     6     5     4     3     2     1

===========================================

0     1     1     1     1     1     0     1  H 7D   octet 1

===========================================

 Length of High Layer Compatibility contents              2

===========================================

1     Coding      Interpretation    Presentation

Ext   standard                                            3

===========================================

0/1   High layer characteristic identification            4

Ext

===========================================

1     Extended high layer characteristics                 4a

Ext    identification

===========================================

Coding Standard (octet 3)

Bits

7 6

===

0 0       CCITT standard

0 1       reserved for other international standards

1 0       national standard

1 1       standard defined for the network

All other values reserved.

Interpretation (octet 3)

Bits

5 4 3

=====

1 0 0     first (primary only) high layer characteristic

          identification to be used in the call.

All other values are reserved.

Presentation metod of protocol profile (octet 3)

Bits

2 1

===

0 1                  high layer protocol profile (without

                     specific specification of attributes)

All other values are reserved.

High layer characterstic identification (octet 4)

Bits

7 6 5 4 3 2 1

=============

0 0 0 0 0 0 1        Telephony

0 0 0 0 1 0 0        Gp 2/3 facsimile

0 1 0 0 0 0 1        Gp 4 facsimile, Class 1

0 1 0 0 1 0 0        Teletex service, basic and mixed mode of

                     operation and facsimile service Group 4,

                     Classes 2 and 3

0 1 0 1 0 0 0        Teletex service, basic and processable

                     mode of operation

0 1 1 0 0 0 1        Teletex service, basic mode of operation

0 1 1 0 0 1 0        Videotex

0 1 1 0 1 0 1        Telex

0 1 1 1 0 0 0        Message Handling Systems (MHS)

1 0 0 0 0 0 1        OSI applications

1 0 1 1 1 1 0        Reserved for maintenance  NOTE

1 0 1 1 1 1 1        Reserved for management   NOTE

1 1 1 1 1 1 1        Reserved

NOTE

When this coding is used, octet 4 may be followed by octet 4a.

Extended high layer characteristics identification (octet 4a)

Bits

7 6 5 4 3 2 1

=============

0 0 0 0 0 0 1        Telephony

0 0 0 0 1 0 0        Gp 2/3 facsimile

0 1 0 0 0 0 1        Gp 4 facsimile, Class 1

0 1 0 0 1 0 0        Teletex service, basic and mixed mode of

                     operation and facsimile service Group 4,

                     Classes 2 and 3

0 1 0 1 0 0 0        Teletex service, basic and processable

                     mode of operation

0 1 1 0 0 0 1        Teletex service, basic mode of operation

0 1 1 0 0 1 0        Videotex

0 1 1 0 1 0 1        Telex

0 1 1 1 0 0 0        Message Handling Systems (MHS)

1 0 0 0 0 0 1        OSI applications

1 0 1 1 1 1 0        Not available for assignment

1 0 1 1 1 1 1        Not available for assignment

1 1 1 1 1 1 1        Reserved


KeypadFacility property of Messages
Keypad facility

Keypad facility

The purpose of the Keypad facility information element is to convey IA5

characters, eg. entered by means of a terminal keypad.

The default maximum length of this information element is 34 octets.

8     7     6     5     4     3     2     1           octet

===========================================

0     0     1     0     1     1     0     0  H 2C     1

===========================================

          Length of Keypad contents                   2

===========================================

          Keypad information                          3

===========================================


LowLayerCompability property of Messages
Low Layer Compability

Low Layer Compatibility

The purpose of the low layer compatibility information element is to provide a means which should be used for compatibility checking by an addressed entity (e.g. a remote user or an interworking unit or a high layer function node addressed by the calling user). The Low Layer Compatibility information element is transferred transparently by an ISDN between the call originating entity (e.g. the calling user) and the addressed entity.

If low layer compatibility negotiation is allowed by the network, the Low Layer Compatibility information element is also passed from the addressed entity to the originating entity.

The maximum length of this information element is 16 octets.

8     7     6     5     4     3     2     1           octet

===========================================

0     1     1     1     1     1     0     0  H 7C     1

===========================================

  Length of the low layer compatibility               2

===========================================

0/1   Coding      Information transfer

      standard    capability                          3

===========================================

1     Negot.0     0     0     0     0     0           3a

Ext   ind.        Spare

===========================================

0/1   Transfer    Information transfer rate

      mode                                            4

===========================================

0/1        Structure    Configura-  Establish-        4a

                        tion        ment

===========================================

1     Symmetry    Information transfer rate           4b

Ext               (destination ==> origination)

===========================================

0/1   0     1     Layer 1 protocol                    5

Ext   L1 ident.   Identification

===========================================

0/1   Synch Nego-    User rate                        5a

      Asynch ti.                                    NOTE 4

===========================================

0/1   Inter-     NIC  NIC  Flow Flow  Spare           5b

      mediate    on   on   contrcontr

      rate       Tx   Rx   on Tx on Rx

===========================================

0/1   Hdr/ Multi Mode LLI  Assig- Inband Spare        5b

      no   frame      Neg  nor/As-Outband           NOTE 3

      Hdr  supp.           signee Neg.

===========================================

0/1   Number of   Number of         Parity            5c

      stop bits   data bits                         NOTE 4

===========================================

1     Duplex      Type of modem                       5d

Ext   type                                          NOTE 4

===========================================

0/1   1     0     Layer 2 protocol                    6

      L2 ident.   Identification

===========================================

1     Optional layer 2 protocol information           6a

Ext

===========================================

0/1   1     1     Layer 3 protocol                    7

      L3 ident.   Identification

===========================================

1     Optional layer 3 protocol information           7a

Ext

===========================================

NOTES TO TABLE

NOTE

If default values are used for all fields of octets 4a and 4b, then these octets shall not be included. If default values are used for all fields of octet 4b, but not for one or more fields of octet 4a, then only octet 4a shall be included. Otherwise, both octets 4a and 4b shall be included.

NOTE

Octet 5b may be present only if octet 5 indicates CCITT standardized rate adaptation V.110/X.30.

NOTE 3

This octet may be present only if octet 5 indicates CCITT standardized rate adaptation V.120.

NOTE 4

This octet may be present only if octet 5 indicates either of the CCITT standardized rate adaptation V.120 or V.110/X.30.

NOTE 5

This octet shall be present if out-band negotiation is required.

Coding standard (octet 3)

Bits

7 6

===

0 0                  CCITT standardized

0 1                  reserved for other internetional standards

1 0                  national standard

1 1                  standard defined for the network

Information transfer capability (octet 3)

Bits

5 4 3 2 1

=========

0 0 0 0 0            speech

0 1 0 0 0            unrestricted digital information

0 1 0 0 1            restricted digital information

1 0 0 0 0            3.1 kHz audio

1 0 0 0 1            7 kHz audio

1 1 0 0 0            video

Negotiation Indicator (octet 3a)

Bit

7

=

0                    out-band negotiation not possible

1                    out-band negotiation possible

When octet 3a is omitted, "out-band negotiation not possible" shall be assumed.

Transfer Mode (octet 4)

Bits

7 6

===

0 0                  circuit-mode

1 0                  packet-mode

Information transfer rate (octets 4 and 4b)

Bits

5 4 3 2 1            Circuit Mode      Packet Mode

=========

0 0 0 0 0                -             This code shal be used for packet M.

1 0 0 0 0            64 kbit/s              -

1 0 0 0 1            2X64 kbit/s            -

1 0 0 1 1            384 kbit/s             -

1 0 1 0 1            1536 kbit/s            -

1 0 1 1 1            1920 kbit/s            -

Structure (octet 4a)

Bits

7 6 5

=====

0 0 0                default (see NOTE)

0 0 1                8 kHz integrity

1 0 0                service data unit integrity

1 1 1                unstructured

NOTE

If octet 4a is omitted, or the structure field is coded "000", then the value of the structure attribute is according to the following:

Transfer Mode        Transfer Capability   Structure

circuit              speech                8 kHz integrity

circuit              unrestricted digital  8 kHz integrity

circuit              restricted digital    8 kHz integrity

circuit              audio                 8 kHz integrity

circuit              video                 8 kHz integrity

packet               unrestricted digital  service data

                                           unit integrity

Configuration (octet 4a)

Bits

4 3

===

0 0                  point-to-point

NOTE

If octet 4a is omitted, the configuration is assumed to be point-to-point.

Establishment (octet 4a)

Bits

2 1

===

0 0                  demand

NOTE

If octet 4a is omitted, demand is assumed.

Symmetry (octet 4b)

Bits

7 6

===

0 0                  bi-directional symmetric

NOTE

If octet 4b is omitted, bidirectional symmetric is assumed.

User information layer 1 protocol (octet 5)

Bits

5 4 3 2 1

=========

0 0 0 0 0       This coding shall not be used

0 0 0 0 1       CCITT standardized rate adaptation

                V.110/X.30. This implies the presence

                of octet 5a and optionally octet 5b,

                5c and 5d as defined below.

0 0 0 1 0       Recommendation G.711 æ-law.

0 0 0 1 1       Recommendation G.711 A-law.

0 0 1 0 0       Recommendation G.721 32 kbit/s ADPCM.

0 0 1 0 1       Recommendation G.722 and G.725 7 kHz audio.

0 0 1 1 0       Recommendation G.7xx 384 kbit/s video.

0 0 1 1 1       Non-CCITT standardized rate adaptation.

                This implies the presence of octet 5a

                and optionally octets 5b, 5c and 5d.

                The use of this codepoint indicates that

                the user rate specified in octet 5a

                is defined in accordance with the non-CCITT

                standardized rate adaptation scheme.

                Additionally, octets 5b, 5c and 5d, if

                present, are defined consistent with the

                specified rate adaptation.

0 1 0 0 0       CCITT standardized rate adaptation

                V.120. This implies the presence of

                octet 5a and 5b and optionally octet

                5c and 5d as defined below.

0 1 0 0 1       CCITT standardized rate adaptation

                X.31 HDLC flag stuffing.

NOTE

If the transfer mode is "circuit mode" and if the information transfer capability is "unrestricted digital" and if the user information layer 1 protocol is not to be identified to the network, octet 5 shall be omitted. If the transfer mode is "packet mode", octet 5 may be omitted. Otherwise octet 5 shall be present.

Synchronous/asynchronous (octet 5a)

Bit

7

=

0                    synchronous

1                    asynchronous

Negotiation (octet 5a)

Bit

6

=

0                    in band negotiation not possible

1                    in band negotiation possible

User rate (octet 5a)

Bits

5 4 3 2 1

=========

0 0 0 0 0            rate indicated by E-bits in Rec. I.460

0 0 0 0 1            0.6 kbit/s Recommendation V.6 and X.1

0 0 0 1 0            1.2 kbit/s Recommendation V.6

0 0 0 1 1            2.4 kbit/s Recommendation V.6 and X.1

0 0 1 0 0            3.6 kbit/s Recommendation V.6

0 0 1 0 1            4.8 kbit/s Recommendation V.6 and X.1

0 0 1 1 0            7.2 kbit/s Recommendation V.6

0 0 1 1 1            8.0 kbit/s Recommendation I.460

0 1 0 0 0            9.6 kbit/s Recommendation V.6 and X.1

0 1 0 0 1            14.4 kbit/s Recommendation V.6

0 1 0 1 0            16 kbit/s Recommendation I.460

0 1 0 1 1            19.2 kbit/s Recommendation V.6

0 1 1 0 0            32 kbit/s Recommendation I.460

0 1 1 1 0            48 kbit/s Recommendation V.6 and X.1

0 1 1 1 1            56 kbit/s Recommendation V.6

1 0 0 0 0            64 kbit/s Recommendation X.1

1 0 1 0 1            0.1345 kbit/s Recommendation X.1

1 0 1 1 0            0.100 kbit/s Recommendation X.1

1 0 1 1 1            0.075/1.200 kbit/s Recommendation V.6 and X.1

1 1 0 0 0            1.200/0.075 kbit/s Recommendation V.6 and X.1

1 1 0 0 1            0.050 kbit/s Recommendation V.6 and X.1

1 1 0 1 0            0.075 kbit/s Recommendation V.6 and X.1

1 1 0 1 1            0.110 kbit/s Recommendation V.6 and X.1

1 1 1 0 0            0.150 kbit/s Recommendation V.6 and X.1

1 1 1 0 1            0.200 kbit/s Recommendation V.6 and X.1

1 1 1 1 0            0.300 kbit/s Recommendation V.6 and X.1

1 1 1 1 1            12 kbit/s Recommendation V.6

*octet 5b for V.110/X.30 rate adaptation*

Intermediate Rate (octet 5b)

Bits

7 6

===

0 0             not used

0 1             8 kbit/s

1 0             16 kbit/s

1 1             32 kbit/s

Network Independent Clock on Transmission (Tx) (octet 5b)

Bit

5

=

0               not require to send data with NIC

1               requires to send data with NIC

Network Independent Clock on Reception (Rx) (octet 5.b)

Bit

4

=

0               cannot accept data with NIC

1               can accept data with NIC

Flow control on Transmission (Tx) (octet 5b)

Bit

3

=

0               not required to send data with flow control

1               required to send data with flow control

Flow control on Reception (Rx) (octet 5b)

Bit

2

=

0               cannot accept data with flow control

                mechanism (sender does not support

                this optional procedure)

1               can accept data with flow control

                mechanism (sender does support this

                optional procedure)

*octet 5b for V.120 rate adaptation*

Rate adaptation header/not header

Bit

7

=

0               rate adaptation header not included

1               rate adaptation header included

Multiple Frame established in Data link

Bit

6

=

0               multiple frame establishment not

                supported. Only UI-frames allowed

1               multiple frame establishment supported

Mode of operation (octet 5b)

Bit

5

=

0               bit transparent mode of operation

1               protocol sensitive mode of operation

Logical Link Identifier Negotiation(octet 5b)

Bit

4

=

0               default, LLI=256 only

1               full protocol negotiation

Assignor/assignee(octet 5b)

Bit

3

=

0               message originator is "default assignee"

1               message originator is "Assignor only"

In-Band/outband negotiation(octet 5b)

Bit

2

=

0               negotiation is done with USER INFORMATION

                messages on a temporary signalling

                connection

1               negotiation is done in-band usnig

                Logical Link zero

Number of Stop and Data Bits and Type of Parity (octet 5c)

Bits

7 6

===

0 0                  not used

0 1                  1 bit

1 0                  1.5 bits

1 1                  2 bits

Number of Data Bits (octet 5c)

Bits

5 4

===

0 0                  not used

0 1                  5 bits

1 0                  7 bits

1 1                  8 bits

Parity (octet 5c)

Bits

3 2 1

=====

0 0 0                odd

0 1 0                even

0 1 1                none

1 0 0                forced to 0

1 0 1                forced to 1

Duplex Type (octet 5d)

Bit

7

=

0                    half duplex

1                    full duplex

Modem Type (octet 5d)

Bits

6 5 4 3 2 1

===========

0 0 0 0 0 1      V.21

0 0 0 0 1 0      V.22

0 0 0 0 1 1      V.22 bis

0 0 0 1 0 0      V.23

0 0 0 1 0 1      V.26

0 0 0 1 1 0      V.26 bis

0 0 0 1 1 1      V.26 ter

0 0 1 0 0 0      V.27

0 0 1 0 0 1      V.27 bis

0 0 1 0 1 0      V.27 ter

0 0 1 0 1 1      V.29

0 0 1 1 0 0      V.32

0 0 1 1 0 1      V.35

1 0 0 0 0 0

    to           Reserved for national use

1 1 1 1 1 1

User information layer 2 protocol (octet 6)

Bits

7 6

===

1 0                  User Information Layer 2 protocol

Bits

5 4 3 2 1

=========

0 0 0 1 0            Recommendation Q.921

0 0 1 1 0            Recommendation X.25 Data Link Layer

User information layer 3 protocol (octet 7)

Bits

5 4 3 2 1

=========

0 0 0 1 0            Recommendation Q.931

0 0 1 1 0            Recommendation X.25 Packet Layer


Moredata property of Messages
More Data

More Data

The more data information element is sent by the user to the network in a USER INFO message and delivered by the network to the destination user in the corresponding USER INFO message.

The use of the more data information element is not supervised by the network.

8     7     6     5     4     3     2     1           octet

===========================================

1     0     1     0     0     0     0     0  H A0       1

===========================================


NetworkSpecificFacilities property of Messages
Network Specific facilities

Network Specific Facilities

The purpose of the Network specific facilities information element is to indicate which network facilities are being invoked.

The Network specific facilities can be repeated up to four times in a message.

The length of Network specific facilities information element is network dependent.

8     7     6     5     4     3     2     1        octet

===========================================

0     0     1     0     0     0     0     0 H 20   1

===========================================

      Length of the Network specific               2

      facilities contents

===========================================

      Length of network identification             3 NOTE 1

===========================================

1     Type of network   Network identification     3.1

Ext   identification    plan

===========================================

0           Network identification                 3.2 NOTE 2

Spare          (IA5 characters)

===========================================

       Network specific facilities                  4

===========================================

NOTE 1

octet 3.1 and 3.2 are only present when the length in octet 3 is non-zero.

NOTE 2

octet 3.2 may be repeated as appropriate.


NotificationIndicator property of Messages
Notification Indicator

Notification Indicator

The purpose of the notification indicator information element is to

indicate information pertaining to a call.

8     7     6     5     4     3     2     1         octet

===========================================

0     0     1     0     0     1     1     1  H 27   1

===========================================

  Length of Notification Indicator contents         2

===========================================

0/1      Notification Description                   3

Ext

===========================================

1        Notification description                   3a

Ext

===========================================

         NotificationDataStructure                  4

===========================================

Notification Description (octet 3)

Bits

7 6 5 4 3 2 1        Meaning

=============

0 0 0 0 0 0 0        user suspended

0 0 0 0 0 0 1        user resumed

0 0 0 0 0 1 0        bearer service change


PartyCategory property of Messages
Party Category

Party Category

The purpose of the party category information element is to indicate the category of a party involved in a call.

NOTE

This information element is only valid for signalling in the Q-reference point.

8     7     6     5     4     3     2     1

===========================================

0     0     1     1     0     0     1     0  H 32    octet 1

===========================================

  Length of Party Category contents                       2

===========================================

1     0     0     0     0    Party Category               3

Ext         Reserved

===========================================

Party Category (octet 3)

Bits

3  2  1        Meaning

=======

0  0  0        Unknown

0  0  1        Extension

0  1  0        Operator

0  1  1        Emergency Operator

All other values are reserved


ProgressIndicator property of Messages
Progress Indicator

Progress Indicator

The purpose of the progress indicator information element is to describe an event which has occurred during the establishment of a call.

8     7     6     5     4     3     2     1

===========================================

0     0     0     1     1     1     1     0  H 1E    octet 1

===========================================

   Length of Progress Indicator contents                  2

===========================================

1     Coding      0           Location                    3

Ext   standard  Spare

===========================================

1                 Progress                                4

Ext               description

===========================================

Coding Standard (octet 3)

Bits

7 6

===

0 0                  CCITT standard

0 1                  ECMA standard

1 0                  national standard

Location (octet 3)

Bits

4 3 2 1

=======

0 0 0 0              user

0 0 0 1              private network serving the local user

0 0 1 0              public network serving the local user

0 0 1 1              transit network

0 1 0 0              public network serving the remote user

0 1 0 1              private network serving the remote user

0 1 1 0              local interface controlled by

                     this signalling link/channel

0 1 1 1              international network

1 0 1 0              network beyond interworking point

Progress Description (octet 4)

CCITT standardized coding

Bits

7 6 5 4 3 2 1        No         Meaning

=============

0 0 0 0 0 0 1        1          Call is not end-to-end

                                ISDN; further call progress

                                information may be available

                                in-band.

0 0 0 0 0 1 0        2          Destination address is

                                non ISDN

0 0 0 0 0 1 1        3          Origination address is

                                non ISDN

0 0 0 0 1 0 0        4          Call has returned to

                                ISDN

0 0 0 1 0 0 0        8          In-band information or

                                an appropriate pattern

                                is now available.

ECMA standardized coding

Bits

7 6 5 4 3 2 1        No      Meaning

=============

0 0 1 0 0 0 0        16      Interworking with public network.

0 0 1 0 0 0 1        17      Interworking with a network unable

                             to supply a release signal.

0 0 1 0 0 1 0        18      Interworking with a network unable

                             to supply a release signal before

                             answer.

0 0 1 0 0 1 1        19      Interworking with a network unable

                             to supply a release signal after

                             answer.

0 0 1 0 1 0 0        20      Interworking with another private

                             network.

0 0 0 1 0 0 0        8       In-band information or

                             an appropriate pattern

                             is now available.


RedirectingNumber property of Messages
Redirecting Number

Redirecting number

The purpose of the Redirecting number information element is to identify the number from which call redirection was invoked. The Redirecting number information element will not be repeated in a message since only one redirection is supported.

8     7     6     5     4     3     2     1

===========================================

0     1     1     1     0     1     0     0  H 74   octet 1

===========================================

   Length of Redirecting Number contents                 2

===========================================

0/1   Type of number   Numbering plan                    3

                                             identification

===========================================

1    Presentation 0     0     0  Screening               3a

Ext  indicator      Spare        indicator

===========================================

0       Number digits (IA5 characters)                   4

===========================================

NOTE

octets 3, 3a and 4 are coded in the same way as Calling Party Number.


RestartIndicator property of Messages
Restart Indicator

Restart Indicator

The purpose of the restart indicator is to identify the class of the facility (i e channel or interface) to be restarted.

8     7     6     5     4     3     2     1

===========================================

0     1     1     1     1     0     0     1  H 78    octet 1

===========================================

   Length of Restart Indicator contents                   2

===========================================

1     0     0     0     0       Class                     3

Ext

===========================================

Class (octet 3)

Bits

3 2 1     Meaning

=====

0 0 0     Indicated channel (NOTE 1)

1 1 0     Single interface (NOTE 2)

1 1 1     All channels in all interfaces

          related to a D-channel. (NOTE 2)

NOTE 1

The channel identification information element must be included in the message to indicate which channel is to be restarted.

NOTE 2

The channel identification information element is not included in the message to indicate the interface to be restarted. Either code point can be used to perform the same function.


SegmentedMessage property of Messages
Segmented Message

Segmented message

The purpose of the Segmented message information element is to indicate that the transmission in which it appears is part of a segmented message, in addition to the use of message type SEGMENT. When included in a message SEGMENT it appears directly after the message type information element.

8     7     6     5     4     3     2     1

===========================================

0     0     0     0     0     0     0     0  H 00    octet 1

===========================================

   Length of Segmented message contents                   2

===========================================

First

segment    Number of segments remaining                   3

ind

===========================================

0          Segmented message type                         4

===========================================

First segment indicator (octet 3)

Bit       Meaning

8

=

0         Subsequent segment for first segment

1         First segment of segmented message

Number of segments remaining (octet 4)

Binary number indicating the number or remaining segments within the messageto be sent.

Segmented message type (octet 4)

Bit 8 is reserved for possible future use as an extension bit.


SendingComplete property of Messages
Sending Complete

Sending complete

The purpose of the Sending complete information element is to optionally indicate completion of called party number.

8     7     6     5     4     3     2     1

===========================================

1     0     1     0     0     0     0     1    H A1    octet 1

           Sending complete

           information element identifier

===========================================


TeleserviceType property of Messages
Teleservice Type

Teleservice Type

The purpose of the teleservice type information element is to request the provision by the network of the indicated teleservice capability.

8     7     6     5     4     3     2     1           octet

===========================================

0     0     0     0     0     1     0     1   H 05    1

===========================================

      Length of Teleservice Type contents             2

===========================================

1     Coding   Interpretation  Presentation           3

Ext   standard

===========================================

1         Teleservice identification                  4

Ext

===========================================

Coding standard (octet 3)

Bits

7 6

===

1 0                  National standard

Interpretation (octet 3)

Bits

5 4 3

=====

1 0 0                First teleservice to be used

                     in the call

Presentation (octet 3)

Bits

2 1

===

0 1                  Teleservice protocol profile

Teleservice identification (octet 4)

Bits

7 6 5 4 3 2 1

=============

0 0 0 0 0 0 1        Telephony

0 1 0 0 0 0 1        GP4 Facsimile

0 1 0 0 0 1 0        GP1-3 Facsimile

0 1 0 1 0 1 0        Timelink

0 1 1 0 0 0 1        Teletex, Teletex64

0 1 1 0 0 1 0        Videotex, Videotex64


TransitCounter property of Messages
Transit Counter

Transit Counter

The purpose of the transit Counter information element is to limit the number of transit points that a call setup request may be routed through, in order to protect the network against indefinite looping.

The maximum transit count is a network dependent value in the range of 0 - 31.

NOTE

This information is only valid for signalling in the Q-reference point.

8     7     6     5     4     3     2     1

===========================================

0     0     1     1     0     0     0     1  H 31    octet 1

===========================================

    Length of Transit Counter contents                    2

===========================================

1     0     0         Transit Count

Ext   Reserved        (binary value)                      3

===========================================


Signal property of Messages
Signal

Signal

The purpose of the Signal information element is to allow the network to optionally convey information to a user regarding tones and alerting signals.

The Signal information element may be repeated in a message.

The Signal information element is coded as shown in the figure below.

8     7     6     5     4     3     2     1

===========================================

0     0     1     1     0     1     0     0  H 34    octet 1

===========================================

        Length of Signal contents                         2

===========================================

             Signal value                                 3

===========================================

Signal value (octet 3)

Bits

8 7 6 5 4 3 2 1

===============

0 0 0 0 0 0 0 0         dial tone on

0 0 0 0 0 0 0 1         ring back tone on

0 0 0 0 0 0 1 0         intercept tone on

0 0 0 0 0 0 1 1         network congestion tone on

0 0 0 0 0 1 0 0         busy tone on

0 0 0 0 0 1 0 1         confirm tone on

0 0 0 0 0 1 1 0         answer tone on

0 0 0 0 0 1 1 1         call waiting tone on

0 0 0 0 1 0 0 0         off-hook warning tone on

0 0 1 1 1 1 1 1         tones off

0 1 0 0 0 0 0 0         alerting on - pattern 0  (NOTE 1)

0 1 0 0 0 0 0 1         alerting on - pattern 1  (NOTE 1)

0 1 0 0 0 0 1 0         alerting on - pattern 2  (NOTE 1)

0 1 0 0 0 0 1 1         alerting on - pattern 3  (NOTE 1)

0 1 0 0 0 1 0 0         alerting on - pattern 4  (NOTE 1)

0 1 0 0 0 1 0 1         alerting on - pattern 5  (NOTE 1)

0 1 0 0 0 1 1 0         alerting on - pattern 6  (NOTE 1)

0 1 0 0 0 1 1 1         alerting on - pattern 7  (NOTE 1)

0 1 0 0 1 1 1 1         alerting off

NOTE 1

The use of these patterns is network dependent.


TransitNetworkSelection property of Messages
Transit Network Selection

Transit Network Selection

The purpose of the Transit network selection information element is to identify one requested transit network. The transit network selection information element may be repeated in a message to select a sequence of transit networks through which a call must pass.

The default maximum length of this information element is market dependent.

The transit network selection information element is coded as shown in the figure below.

8     7     6     5     4     3     2     1

===========================================

0     1     1     1     1     0     0     0  H 78     octet 1

===========================================

Length of Transit Network Selection contents              2

===========================================

1    Type of network     Network identi-

Ext  identification      fication plan                    3

===========================================

0                  Network identification                 4

Spare              (IA5 characters)

===========================================

Type of network identification (octet 3)

Bits

7 6 5

=====

0 0 0     user specified

0 1 0     national network identification

0 1 1     international network identification

Network identification plan (octet 3)

Bits

4 3 2 1

=======

0 0 0 0   unknown

0 0 0 1   carrier identification code

0 0 1 1   data network identification code

Network Identification (octet 4)

These IA5 characters are organized according to the network identification plan specified in octet 3.


UserUser property of Messages
User-User

User-User

The purpose of the User-User information element is to convey information between ISDN users. This information is not interpreted by the network, but rather is carried transparently and delivered to the remote user.

In call control messages, the User-user information element has a market dependent maximum size of 35 or 131 octets.

In the USER INFORMATION message the User-user information element has a market dependent maximum size of 35 or 131 octets.

There are no restrictions on the contents of the user information field.

8     7     6     5     4     3     2     1

===========================================

0     1     1     1     1     1     1     0  H 7E   octet 1

===========================================

      Length of User-User contents                    2

===========================================

            Protocol discriminator                    3

===========================================

                User information                      4

===========================================

Protocol discriminator (octet 3)

Bits

8 7 6 5 4 3 2 1

===============

0 0 0 0 0 0 0 0      user specific protocol

0 0 0 0 0 1 0 0      IA5 characters

0 1 0 0 0 0 0 0      signalling between NT2 entities

                     according to the described

                     protocol.


CallStates property of Messages
Call states

CALL STATES AT THE USER SIDE OF THE INTERFACE

Null (State UO) =>   No call exists.

Call Init (U1)  =>   This call state exists for

                     an outgoing call, as a result

                     of user action requesting

                     call establishment.

Overlap Sending (U2)  =>  This call state exists

                     for an outgoing call while the

                     user is sending call set-up

                     information to the network in

                     the overlap mode.

Outgoing Call Proceeding (U3)  => This state exists

                     for an outgoing call when the

                     network has acknowledged receipt

                     of the information required for

                     the call to proceed and the user

                     is awaiting further network response.

Call Delivered (U4)  =>  This state exists for an

                    outgoing call, when the network

                    has completed processing the call

                    to the point of receiving alerting

                    from the user-network interface

                    indicated by the called address,

                    or an alternate interface specified

                    either by the called user or the

                    network. In addition, in-band tones

                    or announcements may be provided

                    by the network.

Call Present (U6) => This state exists when an incoming

                      call is awaiting a response from the

                      user to call setup from the network.

Call Received (U7) => This state exists for an incoming

                    call when a response/answer from the

                    called user is awaited while alerting.

Connect Request (U8) => This state exists for an incoming

                    call while awaiting receipt from the

                    network of a connect acknowledgement.

Incoming Call Proceeding (U9) => This state exists for an

                 incoming call to the user when the user has

                 acknowledged receipt of the information

                 required for the call to proceed and the

                 network or originating entity is awaiting

                 further user response.

Active (U10) => This state exists when a call is in the

                 end-to-end communication mode.

Disconnect Request (U11) => This state exists in response

                 to a request by the user to disconnect a

                 call, prior to acknowledgement by the network.

Disconnect Indication (U12) => This state exists when the

                 network has indicated disconnect and the

                 user has not yet indicated release.

Release Request (U19) => This state exists in response to a

                 release request, prior to acknowledgement

                 by the network.

Remote Facility Request (U20) => This state exists after a

                 request from the network for the control of a

                 facility, prior to user response.

Local Facility Request (U21) => This state exists after a

                request by the user to the network for the

                control of a facility, prior to network response.

Overlap receiving state (U25) => This state exists for an

                incoming call while the network is sending

                call setup information to the user in the

                overlap mode.


Timers property of Messages
Timers

Timers in the network side

Timer      Default time-out     State of call        Cause for start        Normal stop                          At the first

number    value                                                                                                                                expiry

==================================================================================================================================

T301       Minimum 3 min     Call received        ALERT                  CONNECT                          Clear call

                                                                            received                  received

T302       10-15 s (NOTE 5)    Overlap sending   SETUP ACK sent  With sending complete       Clear if call information

                                                                             Receipt of INFO    indication, or network         determined to be definitely

                                                                             restarts T302         alert, or connect request      incomplete; else send

                                                                                                            received                               CALL PROC

T303      4 s (NOTE 1)             Call present           SETUP sent         ALERT,                                Retransmit SETUP

                                                                                                          CONNECT CALL PROC     restart T303. If REL

                                                                                                          SETUP ACK received,          COMPLETE has

                                                                                                          REL COMPLETE received       been received,

                                                                                                          if SETUP sent on point-point      clear the call.

                                                                                                          data link

T304      20 s                        Overlap receiving   SETUP ACK      Send INFO;                             Clear the call

             (provisional values)                                received               receive CALL PROC,

                                                                             Sending of INFO ALERT or

                                                                             restarts T304       CONNECT

T305      30 s                        Disconnect             DISC without       REL or DISC                          Network sends

                                              indication               progress               received                                   REL

                                                                             indicator No. 8

                                                                             sent

T306      30 s (NOTE 6)       Disconnect               DISC with            REL or DISC                          Stop the

                                           indication                 progress                received                                  tone/announcement

                                                                            indicator No. 8                                                     Send REL

                                                                             sent

T307       3 min                  Null                         SUSPEND ACK    RES ACK sent                      Clear the network

                                                                           sent                                                                        connection

                                                                                                                                                         Release call

                                                                                                                                                         identity

T308         4 s (NOTE 1)      Release request       REL sent                REL COMPLETE                 Retransmit REL

                                                                                                           or REL received                    and restart T308

T309        90 s                    Any stable state      Data link                Data link                               Clear network

                                                                           disconnection.        reconnected                           connection

                                                                           Calls in stable                                                      Release B-

                                                                           states are not lost                                                 channel and

                                                                                                                                                        call reference

T310        10 s (NOTE 7)     Incoming Call         CALL PROC         ALERT,                               Clear call in

                                           Proceeding              received                  CONNECT or                     accordance with

                                                                                                          DISC received                      Q931 5.2.5.3

                                                                                                          If DISC, retain

                                                                                                          cause and

                                                                                                         continue timing

T312        T303 + 2 s         Call Present,         SETUP sent             Timeout                                (NOTE 4)

                                            Call Abort, etc.    or resent on

                                                                         broadcast data

                                                                         link

T314         4 s                    Receiving              Message                  Last message                          Discard

                                           segmented            segment                   segment                                  message

                                           message               received                   received

T316       2 min                 Restart                 RESTART sent        RESTART ACK                   RESTART may

                                          request                                                   received                                 be retransmittede

                                                                                                                                                       several times

T317      (NOTE 3)             Restart                 RESTART                Internal clearing                     Maintenance

                                                                      received                     of call references                   notification

T320       30 s(NOTE 8)     a)For B-               a)For B-                    Call request packet                a)For B-

                                          channel                channel                     received; or                            channel access:

                                          access:                 access:                      incoming call                         disconnect

                                          active                  connection                 packet delivered;                   link layer and

                                          b)For D-             b)For D-                    or DISC received;                  initiate clearing

                                          channel               channel                      or for D-channel                    b)For D-

                                          access: null        access: DL-               access DL-                             channel

                                                                     ESTAB-                    RELEASE                             access: send

                                                                     LISHMENT              indication                              DL-RELEASE

                                                                    Confirmation              received                                 request

                                                                    or DL-ESTAB

                                                                    LISHMENT

                                                                    indication

                                                                    received

                                                                   c)Last logical

                                                                   channel, cleared

                                                                    received

T321        30 s        Any call state             D-channel failure         Response to layer 3     Send DL-ESTAB

                                                                                                       message received          LISHMENT

                                                                                                                                             request on both

                                                                                                                                             D-channels

T322        4 s            Any all state             STATUS ENQ         STATUS DISC REL       STATUS ENQ may

                                                                   sent                          or REL COMPLETE        be retransmitted

                                                                                                    received                             several times

NOTES

1   This default value assumes the use of default values at layer 2 (i.e. N200 + 1] times T200). Whether these values should be modified when layer 2 default values are modified by an automatic negotiation procedure is for further study.

3   The value of this timer is implementation dependent but should be less than the value of T316.

4   If in the call abort state, the call reference is released. Otherwise, no action is taken on expiry of timer T312.

5   The value of timer T302 may vary beyond these limits, e.g. as a result of called party number analysis.

6   The value of timer T306 may depend on the length of the announcement.

7   The value of timer T310 may be different in order to take into account the characteristics of a private network.

8   This value may vary by network-user agreement.