16 Messages/Procedures and their contents

23.2053GPPBearer-independent circuit-switched core networkRelease 17Stage 2TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

This clause contains the detailed description of the information flows used in bearer independent CS core network.

Each Information Element, IE, is marked as (M) Mandatory, (C) Conditional or (O) Optional. A mandatory information element shall always be present. A conditional information shall be present if certain conditions are fulfilled; if those conditions are not fulfilled it shall be absent. An optional information element may be present or absent, at the discretion of the application at the sending entity. This categorisation is a functional classification, i.e., stage 2 information and not a stage 3 classification to be used for the protocol.

The stage 2 and stage 3 message and information element names are not necessarily identical.

16.1 Messages between (G)MSC servers

Table 16.1 indicates messages between (G)MSC servers in Nc interface. Only the new messages and information elements required by the bearer independent CS core network are shown.

Table 16.1: Messages between (G)MSC servers

Message	Message direction	Information element name	Information element required	Information element description
Initial Address	Forward	Bearer Establishment Direction	M	This information element indicates that the direction of bearer establishment.
		Bearer Address	C	This information element indicates the bearer address of the MGW used by the preceding node. This information element is included when an AAL2 bearer is establish ed using backward bearer establishment control protocol. Otherwise the information element is optional.
		Binding Reference	C	This information element indicates the bearer identifier in the MGW used by the preceding node. This information element is included when an AAL2 bearer is established using backward bearer establishment control protocol. Otherwise the information element is optional.
		MGW-id	O	This information element indicates the MGW selected by the preceding node.
		Bearer Characteristics	M	This information element indicates the characteristics of the bearer.
		Tunnel Indicator	O	This information element indicates either that tunnelling is to be used or tunnelling is supported.
		Tunnel data	O	This information element contains the tunnel data that is provided between MGWs.
Bearer Information	Backward	Bearer Address	C	This information element indicates the bearer address of the MGW used by the succeeding node. This information element is included when an AAL2 bearer is established using forward bearer establishment control protocol. Otherwise the information element is optional.
		Binding Reference	C	This information element indicates the bearer identifier in the MGW used by the succeeding node. This information element is included when an AAL2 bearer is established using forward bearer establishment control protocol. Otherwise the information element is optional.
		MGW-id	O	This information element indicates the MGW selected by the succeeding node.
		Tunnel Indicator	O	This information element indicates that tunnelling is used.

Tunnel Information	Both	Tunnel Indicator	M	This information element indicates that the message contains tunnelling information.
Tunnel Information	Both	Tunnel data	M	This information element contains the tunnel data that is provided between MGWs.
Start DTMF	Both	Start DTMF indicator	M	This information element indicates that the message is used for Start DTMF.
Start DTMF	Both	Digit	M	This information element indicates the digit for DTMF tone generation.
Start DTMF Ack	Both	Start DTMF Ack indicator	M	This information element indicates that the message is used for Start DTMF Ack.
Stop DTMF	Both	Stop DTMF indicator	M	This information element indicates that the message is used for Stop DTMF.
Stop DTMF Ack	Both	Stop DTMF Ack indicator	M	This information element indicates that the message is used for Stop DTMF Ack.

16.2 Procedures between (G)MSC server and MGW

The clauses below indicate the procedures used between (G)MSC server and MGW in Mc interface. The procedures are logical, i.e. message identifiers are not part of the protocol. Several logical procedures can be combined into one H.248 command in order to perform required transactions. If several logical procedures are combined, only one context/context request and only one bearer termination/bearer termination request is sent in the H.248 command. Exemption is the Change Flow Direction procedure, where the two bearer terminations are related to a change of the context and not to a command of the bearer termination. All the procedures below describe a successful operation. If the procedure is rejected, a Command Reject is sent back to the entity that sent the command request.

16.2.1 Change Flow Direction

This procedure is used to change the flow direction between bearer terminations within the context.

Table 16.2: Procedures between (G)MSC server and MGW: Change Flow Direction

Procedure	Initiated	Information element name	Information element required	Information element description
Change Flow Direction	(G)MSC-S	Context/Context Request	M	This information element indicates the existing context or a new context where the flow direction is changed.
		Bearer Termination 1/ Bearer Termination 1 Request	M	This information element indicates the existing bearer termination or a new bearer termination from where the new flow direction is applied.
		Bearer Termination 2/ Bearer Termination 2 Request	M	This information element indicates the existing bearer termination or a new bearer termination where to the new flow direction is applied.
		Flow Direction	M	This information element indicates the flow direction from the bearer termination 1 to bearer termination 2 within the context.
Change Flow Direction Ack	MGW	Context	M	This information element indicates the context where the command was executed.

NOTE 1: This procedure may be combined with Prepare Bearer, Prepare_IP_Transport, Establish Bearer, Reserve Circuit, Reserve RTP Connection Point, Configure RTP Connection Point or Reserve and Configure RTP Connection Point, Join Bearer Termination or Isolate Bearer Termination procedure. This list of procedures is not exhaustive.

NOTE 2: Only one of the bearer terminations can be a new bearer termination within this procedure.

16.2.2 Join Bearer Termination

This procedure is used to join a bearer termination with other bearer terminations within the context.

Table 16.3: Procedures between (G)MSC server and MGW: Join Bearer Termination

Procedure	Initiated	Information element name	Information element required	Information element description
Join Bearer Termination	(G)MSC-S	Context	M	This information element indicates the context where the bearer termination is joined.
Join Bearer Termination	(G)MSC-S	Bearer Termination/Bearer Termination Request	M	This information element indicates the existing bearer termination or requests a new bearer termination to be joined with the other bearer terminations within the context.
Join Bearer Termination Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Join Bearer Termination Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.3 Isolate Bearer Termination

This procedure is used to isolate one bearer termination from the other bearer terminations within the context.

Table 16.4: Procedures between (G)MSC server and MGW: Isolate Bearer Termination

Procedure	Initiated	Information element name	Information element required	Information element description
Isolate Bearer Termination	(G)MSC-S	Context/Context Request	M	This information element indicates the existing context or a new context where to the bearer termination is isolated.
Isolate Bearer Termination	(G)MSC-S	Bearer Termination/Bearer Termination Request	M	This information element indicates the existing bearer termination or requests a new bearer termination to be isolated from the other bearer terminations within the context.
Isolate Bearer Termination Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Isolate Bearer Termination Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.4 Establish Bearer

This procedure is used to request a bearer establishment.

Table 16.5: Procedures between (G)MSC server and MGW: Establish Bearer

Procedure	Initiated	Information element name	Information element required	Information element description
Establish Bearer (G)MSC-S		Context/Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
		Bearer Termination/Bearer Termination Request	M	This information element indicates the existing bearer termination or requests a new bearer termination for the bearer to be established.
		Bearer Establishment Request	M	This information element requests establishment of a bearer.
		Destination Binding Reference	C	This information element indicates the bearer identifier in the destination MGW. This information element shall be included when requesting the establishment of an AAL2 bearer. Otherwise the information element is optional.
		Destination Bearer Address	C	This information element indicates the bearer address of the destination MGW. This information element shall be included when requesting the establishment of an AAL2 bearer. Otherwise the information element is optional.
		Bearer Characteristics	M	This information element indicates the characteristics of the bearer connection.
		Bearer Service Characteristics	C	This information element indicates the bearer service requested by the user. This information element is not included if the Codec information element is provided. It may be included for a non-speech / non SCUDIF multimedia call (see3GPP TS 23.172 [38], 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6]).
		Notify Bearer Event	O	This information element requests a notification of an established bearer, a released bearer, a modified bearer or a bearer modification failure.
		Tunnel Support	O	This information element indicates the support of tunnel data transfer and when to send tunnel data. In 29.232 this information element is defined in the Tunnel Information down procedure.
		Circuit Switched Data	C	This information element indicates the PLMN bearer capabilities and when applicable GSM channel coding. This information element shall be included according to 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6] for a non-speech / non SCUDIF multimedia call (see 3GPP TS 23.172 [38])by the MSC server, or by the anchor-MSC in case of inter-MSC handover, for an anchor MGW network termination.
		Codec	C	This information element indicates the speech coding format to be used for the bearer. This information element is included for a speech call for a network side bearer termination.
		Framing Protocol	O	This information element indicates the framing protocol to be used for the bearer.
		Call Type Discrimination	O	This information element supports modem signalling for GTT feature. NOTE
		Text Telephone	O	This information element supports interworking with PSTN text telephone. NOTE
		Notify termination heartbeat	C	This information element requests termination heartbeat indications. This information element shall be included when requesting a new bearer termination. Otherwise the information element is optional.
		IP Realm Identifier	O	This information element indicates the IP realm of the IP termination.
		Number of desired listener context terminations	O	This information element indicates the number of desired terminations for a listener context in a VGCS or VBS call. It should be included in the first ADD request which establishes a Listener context.
Establish Bearer Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Establish Bearer Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.
NOTE: Procedures for use of Text Telephony indication and Call Type discrimination are not defined.

16.2.5 Prepare Bearer

This procedure is used to prepare for a bearer establishment.

Table 16.6: Procedures between (G)MSC server and MGW: Prepare Bearer

Procedure	Initiated	Information element name	Information element required	Information element description
Prepare Bearer (G)MSC-S		Context/Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
		Bearer Termination Request	M	This information element requests a new bearer termination for the bearer to be established.
		Binding Reference Request	C	This information element requests the bearer identifier in the MGW. This information element shall be included when preparing the establishment of an AAL2 bearer. Otherwise the information element is optional.
		Bearer Address Request	C	This information element requests the bearer address of the MGW. This information element shall be included when preparing the establishment of an AAL2 bearer. Otherwise the information element is optional.
		Sender Binding Reference	O	This information element indicates the bearer identifier of the sending MGW.
		Sender Bearer Address	O	This information element indicates the bearer address of the sending MGW.
		Bearer Characteristics	M	This information element indicates the requested characteristics of the bearer connection.
		Bearer Service Characteristics	C	This information element indicates the bearer service requested by the user. This information element is not included if the Codec information element is provided. It may be included for a data call (see 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6]).
		Notify Bearer Event	O	This information element requests a notification of an established bearer, a released bearer, a modified bearer or a bearer modification failure.
		Notify Bearer Modification	O	This information element requests a notification that bearer modification of the established bearer is allowed. This information element may be included for access bearer assignment.
		Tunnel Support	O	This information element indicates the support of tunnel data transfer and when to send tunnel data. In 3GPP TS 29.232 [6] this information element is defined in the Tunnel Information down procedure.
		Circuit Switched Data	C	This information element indicates the PLMN bearer capabilities and when applicable GSM channel coding and user bit rate. This information element shall be included according to 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6] for a non-speech call by the MSC server, or by the anchor-MSC in case of inter-MSC handover, for a radio access network termination and for an anchor MGW network termination.
		Codec	C	This information element indicates the speech or multimedia coding format to be used for the bearer. This information element is included for a speech call and may be included for a SCUDIF multimedia call (see3GPP TS 23.172 [38], 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6]).
		Framing Protocol	O	This information element indicates the framing protocol to be used for the bearer.
		Cellular Text telephony modem	C	This information element indicates the need of CTM function.
		Notify termination heartbeat	M	This information element requests termination heartbeat indications.
		Number of needed conference terminations	O	This information element indicates the number of conference ports needed for that VGCS or VBS call. It shall be included in the first ADD request which establishes the Multiparty context.
		IP Realm Identifier	O	This information element indicates the IP realm of the IP termination.
Prepare Bearer Ack	MGW	Context	M	This information element indicates the context where the command was executed.
		Bearer Termination	M	This information element indicates the bearer termination where the command was executed.
		Binding Reference	C	This information element indicates the bearer identifier in the MGW. This information element is included if requested in the Prepare Bearer request.
		Bearer Address	C	This information element indicates the bearer address of the MGW. This information element is included if requested in the Prepare Bearer request.

16.2.6 Reserve Circuit

This procedure is used to select a TDM circuit in the MGW.

Table 16.7: Procedures between (G)MSC server and MGW: Reserve Circuit

Procedure	Initiated	Information element name	Information element required	Information element description
Reserve Circuit (G)MSC-S		Context/Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
		Bearer Termination	M	This information element indicates the physical bearer termination for the TDM circuit.
		Circuit Switched Data	C	This information element indicates the PLMN bearer capabilities and GSM channel coding. This information element shall be included according to 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6] for a non-speech call by the MSC server, or by the anchor-MSC in case of inter-MSC handover, for a radio access network side bearer termination.
		Bearer Service Characteristics	C	This information element indicates the bearer service requested by the user. This information element is included if no Circuit Switched Data information element is provided.
		Cellular Text telephony modem	C	This information element indicates the need of CTM function.
		Notify Released Bearer	O	This information element requests a notification of a released bearer
		Notify termination heartbeat	O	This information element requests termination heartbeat indications.
		Number of desired listener context terminations	O	This information element indicates the number of desired terminations for a listener context in a VGCS or VBS call. It should be included in the first ADD request which establishes a Listener context.
Reserve Circuit Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Reserve Circuit Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed..

16.2.7 Change Through-Connection

This procedure is used to change the through-connection in the bearer termination.

Table 16.8: Procedures between (G)MSC server and MGW: Change Through-Connection

Procedure	Initiated	Information element name	Information element required	Information element description
Change Through-Connection	(G)MSC-S	Context/Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
		Bearer Termination/Bearer Termination Request	M	This information element indicates the existing bearer termination or requests a new bearer termination where the through-connection is changed.
		Through-Connection	M	This information element indicates the through-connection of the bearer termination.
Change Through-Connection Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Change Through-Connection Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

NOTE: This procedure may be combined with Prepare Bearer, Prepare_IP_Transport, Establish Bearer, Reserve Circuit, Reserve RTP Connection Point , Configure RTP Connection Point or Reserve and Configure RTP Connection Point, Join Bearer Termination, Isolate Bearer Termination or Release Bearer procedure. This list of procedures is not exhaustive.

16.2.8 Activate Interworking Function

This procedure is used to activate the interworking function.

Table 16.9: Procedures between (G)MSC server and MGW: Activate Interworking Function

Procedure	Initiated	Information element name	Information element required	Information element description
Activate Interworking Function	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the interworking function is activated.
		Circuit Switched Data Activate	M	This information element requests to activate the interworking function.
		Circuit Switched Data	O	This information element indicates the request for IWF protocol negotiation result and rate change indication.
Activate Interworking Function Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Activate Interworking Function Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.9 Release Bearer

This procedure is used to release the bearer.

Table 16.10: Procedures between (G)MSC server and MGW: Release Bearer

Procedure	Initiated	Information element name	Information element required	Information element description
Release Bearer	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination for the bearer to be released.
		Bearer Release Request	M	This information element requests release of a bearer.
		Release Cause	O	This information element indicates the cause of a bearer release.
Release Bearer Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Release Bearer Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.10 Bearer Established

This procedure is used to notify the established bearer.

Table 16.11: Procedures between (G)MSC server and MGW: Bearer Established

Procedure	Initiated	Information element name	Information element required	Information element description
Bearer Established	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the bearer was established.
		Bearer Established	M	This information element notifies a bearer establishment.
Bearer Established Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Bearer Established Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.11 Bearer Released

This procedure is used to notify the released bearer or failed bearer establishment.

Table 16.12: Procedures between (G)MSC server and MGW: Bearer Released

Procedure	Initiated	Information element name	Information element required	Information element description
Bearer Released	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the bearer was released.
		Bearer Released	M	This information element notifies a bearer release.
		Release Cause	M	This information element indicates the cause of a bearer release.
Bearer Released Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Bearer Released Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.12 Release Termination

This procedure is used to release the bearer termination.

Table 16.13: Procedures between (G)MSC server and MGW: Release Termination

Procedure	Initiated	Information element name	Information element required	Information element description
Release Termination	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
Release Termination	(G)MSC-S	Bearer Termination	M	This information element indicates the bearer termination to be released.
Release Termination Ack	MGW	Context	M	This information element indicates the context where the command was executed.
		Bearer Termination	M	This information element indicates the bearer termination where the command was executed.
		T.140 data statistics	C	Number of t.140 data bits transmitted over the termination

16.2.13 Tunnel Information Up

This procedure is used to transfer tunnel data from the MGW to the (G)MSC server.

Table 16.14: Procedures between (G)MSC server and MGW: Tunnel Information Up

Procedure	Initiated	Information element name	Information element required	Information element description
Tunnel Information Up	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination from where the tunnel data is sent.
		Tunnel Data	M	This information element contains the tunnel data that is provided between MGWs.
Tunnel InformationUp Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Tunnel InformationUp Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.14 Tunnel Information Down

This procedure is used to transfer tunnel data from the (G)MSC server to the MGW.

Table 16.15: Procedures between (G)MSC server and MGW: Tunnel Information

Procedure	Initiated	Information element name	Information element required	Information element description
Tunnel Information Down	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where to the tunnel data is sent.
		Tunnel Data	M	This information element contains the tunnel data that is provided between MGWs.
Tunnel Information Down Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Tunnel Information Down Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

NOTE: This procedure may be combined with Prepare Bearer or Establish Bearer procedure.

16.2.15 Send Tone

This procedure is used to send a tone.

Table 16.16: Procedures between (G)MSC server and MGW: Send Tone

Procedure	Initiated	Information element name	Information element required	Information element description
Send Tone (G)MSC-S		Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination/Bearer Termination Request	M	This information element indicates the existing bearer termination or requests a new bearer termination where the tone is sent.
		Tone	M	This information element indicates the tone to be generated.
		Notify Tone Completion	O	This information element requests a notification of a completed tone.
		Tone Direction	O	This information element indicates the tone direction in the bearer termination.
		Tone Timing	O	This information element indicates the time for the tone.
		Notify termination heartbeat	C	This information element requests termination heartbeat indications. This information element shall be included when requesting a new ephemeral bearer termination.
Send Tone Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Send Tone Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

NOTE: This procedure may be combined with Join Bearer Termination or Isolate Bearer Termination procedure.

16.2.16 Stop Tone

This procedure is used to stop the tone.

Table 16.17: Procedures between (G)MSC server and MGW: Stop Tone

Procedure	Initiated	Information element name	Information element required	Information element description
Stop Tone	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the tone is stopped.
		Stop Tone	M	This information element requests that tone generation is stopped.
Stop Tone Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Stop Tone Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.17 Play Announcement

This procedure is used to play an announcement.

Table 16.18: Procedures between (G)MSC server and MGW: Play Announcement

Procedure	Initiated	Information element name	Information element required	Information element description
Play Announcement (G)MSC-S		Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination/Bearer Termination Request	M	This information element indicates the existing bearer termination or requests a new bearer termination where the announcement is sent.
		Announcement	M	This information element indicates the announcement to be played.
		Notify Announcement Completion	O	This information element requests a notification of a completed announcement.
		Announcement Direction	O	This information element indicates the announcement direction in the bearer termination.
		Announcement Timing	O	This information element indicates the time for the announcement.
		Notify termination heartbeat	C	This information element requests termination heartbeat indications. This information element shall be included when requesting a new ephemeral bearer termination.
Play Announcement Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Play Announcement Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

NOTE: This procedure may be combined with Join Bearer Termination or Isolate Bearer Termination procedure.

16.2.18 Stop Announcement

This procedure is used to stop the announcement.

Table 16.19: Procedures between (G)MSC server and MGW: Stop Announcement

Procedure	Initiated	Information element name	Information element required	Information element description
Stop Announcement	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the announcement is stopped.
		Stop Announcement	M	This information element requests that announcement playing is stopped.
Stop Announcement Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Stop Announcement Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.19 Announcement Completed

This procedure is used to notify the completed announcement.

Table 16.20: Procedures between (G)MSC server and MGW: Announcement Completed

Procedure	Initiated	Information element name	Information element required	Information element description
Announcement Completed	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the announcement was completed.
		Announcement Completed	M	This information element indicates completion of the announcement.
Announcement Completed Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Announcement Completed Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.20 Tone Completed

This procedure is used to notify the completed tone.

Table 16.21: Procedures between (G)MSC server and MGW: Tone Completed

Procedure	Initiated	Information element name	Information element required	Information element description
Tone Completed	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the tone was completed.
		Tone Completed	M	This information element indicates completion of the tone.
Tone Completed Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Tone Completed Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.21 Detect DTMF

This procedure is used to request detection of a DTMF tone.

Table 16.22: Procedures between (G)MSC server and MGW: Detect DTMF

Procedure	Initiated	Information element name	Information element required	Information element description
Detect DTMF	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination/Bearer Termination Request	M	This information element indicates the existing bearer termination or requests a new bearer termination where the DTMF tone detection is requested.
		Digit	M	This information element requests MGW to detect a DTMF tone.
Detect DTMF Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Detect DTMF Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

NOTE This procedure may be combined with Prepare Bearer, Prepare_IP_Transport, Establish Bearer, Reserve Circuit, Reserve RTP Connection Point procedure, Configure RTP Connection Point or Reserve and Configure RTP Connection Point. This list of procedures is not exhaustive.

16.2.22 Stop DTMF Detection

This procedure is used to stop detection of the DTMF tone.

Table 16.23: Procedures between (G)MSC server and MGW: Stop DTMF Detection

Procedure	Initiated	Information element name	Information element required	Information element description
Stop DTMF Detection	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the DTMF tone detection is stopped.
		Stop DTMF Detection	M	This information element requests that DTMF tone detection is stopped.
Stop DTMF Detection Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Stop DTMF Detection Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.23 Report DTMF

This procedure is used to report a detected DTMF tone.

Table 16.24: Procedures between (G)MSC server and MGW: Report DTMF

Procedure	Initiated	Information element name	Information element required	Information element description
Report DTMF	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the DTMF tone was detected.
		Digit	M	This information element reports the detected DTMF tone.
Report DTMF Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Report DTMF Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.24 Send DTMF

This procedure is used to request sending of a DTMF tone.

Table 16.25: Procedures between (G)MSC server and MGW: Send DTMF

Procedure	Initiated	Information element name	Information element required	Information element description
Send DTMF	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination/Bearer Termination Request	M	This information element indicates the existing bearer termination or requests a new bearer termination where the DTMF tone generation is requested.
		Digit	M	This information element requests MGW to generate a DTMF tone.
		DTMF Tone Timing	O	This information element indicates the time for the DTMF tone in the bearer termination.
Send DTMF Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Send DTMF Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.25 Stop DTMF

This procedure is used to stop sending of the DTMF tone.

Table 16.26: Procedures between (G)MSC server and MGW: Stop DTMF

Procedure	Initiated	Information element name	Information element required	Information element description
Stop DTMF	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the DTMF tone generation is stopped.
		Stop DTMF	M	This information element requests that DTMF tone generation is stopped.
Stop DTMF Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Stop DTMF Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.26 MGW Out-of-Service/ Maintenance locking

This procedure is used to indicate that the MGW will go out of service or is maintenance locked.

Table 16.27: Procedures between (G)MSC server and MGW: MGW Out-of-Service or Maintenance Locked

Procedure	Initiated	Information element name	Information element required	Information element description
MGW Out-of-Service/ Maintenance locked	MGW	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates the root termination for the command.
		Reason	M	This information element indicates the reason for service change.
		Method	M	This information element indicates the method for service change.
MGW Out-of-Service/ Maintenance locked Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
MGW Out-of-Service/ Maintenance locked Ack	(G)MSC-S	Root Termination	M	This information element indicates the root termination where the command was executed.

16.2.27 MGW Communication Up

This procedure is used to indicate that the MGW is back in service.

Table 16.28: Procedures between (G)MSC server and MGW: MGW Communication Up

Procedure	Initiated	Information element name	Information element required	Information element description
MGW Communication Up	MGW	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates the root termination for the command.
		Reason	M	This information element indicates the reason for service change.
		Method	M	This information element indicates the method for service change.
MGW Communication Up Ack (G)MSC-S		Context	M	This information element indicates the context where the command was executed.
		Root Termination	M	This information element indicates the root termination where the command was executed.
		(G)MSC-S Address	O	This information element indicates the (G)MSC server signalling address to which the MGW should preferably attempt to re-register.

16.2.28 MGW Restoration

This procedure is used to indicate the MGW failure or recovery.

Table 16.29: Procedures between (G)MSC server and MGW: MGW Restoration

Procedure	Initiated	Information element name	Information element required	Information element description
MGW Restoration	MGW	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates the root termination for the command.
		Reason	M	This information element indicates the reason for the service change.
		Method	M	This information element indicates the method for service change.
MGW Restoration Ack (G)MSC-S		Context	M	This information element indicates the context where the command was executed.
		Root Termination	M	This information element indicates the root termination where the command was executed.
		(G)MSC-S Address	O	This information element indicates the (G)MSC server signalling address to which the MGW should preferably attempt to re-register.

16.2.29 MGW Register

This procedure is used to register the MGW.

Table 16.30: Procedures between (G)MSC server and MGW: MGW Register

Procedure	Initiated	Information element name	Information element required	Information element description
MGW Register	MGW	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates the root termination for the command.
		Reason	M	This information element indicates the reason for the service change.
		Method	M	This information element indicates the method for service change.
		Protocol Version	M	This information element indicates the protocol version for Mc interface requested by the MGW.
		Service Change Profile	M	This information element indicates the profile for the Mc interface requested by the MGW.
MGW Register Ack (G)MSC-S		Context	M	This information element indicates the context where the command was executed.
		Root Termination	M	This information element indicates the root termination where the command was executed.
		Protocol Version	O	This information element indicates the protocol version for Mc interface supported by the (G)MSC server.
		Service Change Profile	O	This information element indicates the profile for the Mc interface supported by the (G)MSC Server.
		(G)MSC-S Address	O	This information element indicates the (G)MSC server signalling address to which the MGW should preferably attempt to re-register.

16.2.30 MGW Re-register

This procedure is used to re-register the MGW.

Table 16.31: Procedures between (G)MSC server and MGW: MGW Re-register

Procedure	Initiated	Information element name	Information element required	Information element description
MGW Re-register	MGW	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates the root termination for the command.
		Reason	M	This information element indicates the reason for the service change.
		Method	M	This information element indicates the method for service change.
		Protocol Version	M	This information element indicates the protocol version for Mc interface requested by the MGW.
		Service Change Profile	M	This information element indicates the profile for the Mc interface requested by the MGW.
MGW Re-register Ack (G)MSC-S		Context	M	This information element indicates the context where the command was executed.
		Root Termination	M	This information element indicates the root termination where the command was executed.
		Protocol Version	O	This information element indicates the protocol version for Mc interface supported by the (G)MSC server.
		Service Change Profile	O	This information element indicates the profile for the Mc interface supported by the (G)MSC Server.
		(G)MSC-S Address	O	This information element indicates the (G)MSC server signalling address to which the MGW should preferably attempt to re-register.

16.2.31 (G)MSC Server Ordered Re-register

This procedure is used by the (G)MSC server to request the MGW to register itself.

Table 16.32: Procedures between (G)MSC server and MGW: (G)MSC Server Ordered Re-register

Procedure	Initiated	Information element name	Information element required	Information element description
(G)MSC Server Ordered Re- register	(G)MSC-S	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates the root termination for the command.
		Reason	M	This information element indicates the reason for the service change.
		(G)MSC-S Address	O	This information element indicates the (G)MSC server signalling address.
(G)MSC Server Ordered Re- register Ack	MGW	Context	M	This information element indicates the context where the command was executed.
(G)MSC Server Ordered Re- register Ack	MGW	Root Termination	M	This information element indicates the root termination where the command was executed.

16.2.32 (G)MSC Server Restoration

This procedure is used to indicate the (G)MSC server failure or recovery.

Table 16.33: Procedures between (G)MSC server and MGW: (G)MSC Server Restoration

Procedure	Initiated	Information element name	Information element required	Information element description
(G)MSC Server Restoration	(G)MSC-S	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates the root termination for the command.
		Reason	M	This information element indicates the reason for the service change.
		Method	M	This information element indicates the method for service change.
(G)MSC Server Restoration Ack	MGW	Context	M	This information element indicates the context where the command was executed.
(G)MSC Server Restoration Ack	MGW	Root Termination	M	This information element indicates the root termination where the command was executed.

16.2.33 (G)MSC Server Out of Service

This procedure is used to indicate that (G)MSC server has gone out of service.

Table 16.34: Procedures between (G)MSC server and MGW: (G)MSC Server Out of Service

Procedure	Initiated	Information element name	Information element required	Information element description
(G)MSC Server Out of Service	(G)MSC-S	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates the root termination for the command.
		Reason	M	This information element indicates the reason for the service change.
		Method	M	This information element indicates the method for service change.
(G)MSC Server Out of Service Ack	MGW	Context	M	This information element indicates the context where the command was executed.
(G)MSC Server Out of Service Ack	MGW	Root Termination	M	This information element indicates the root termination where the command was executed.

16.2.34 Termination Out-of-Service

This procedure is used to indicate that physical termination(s) will go out of service.

Table 16.35: Procedures between (G)MSC server and MGW: Termination Out-of-Service

Procedure	Initiated	Information element name	Information element required	Information element description
Termination Out-of-Service	MGW	Context	M	This information element indicates the context for the command.
		Bearer Termination	M	This information element indicates the bearer termination(s) for the command.
		Reason	M	This information element indicates the reason for service change.
		Method	M	This information element indicates the method for service change.
Termination Out-of-Service Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Termination Out-of-Service Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.35 Termination Restoration

This procedure is used to indicate that physical termination(s) are back in service.

Table 16.36: Procedures between (G)MSC server and MGW: Termination Restoration

Procedure	Initiated	Information element name	Information element required	Information element description
Termination Restoration	MGW	Context	M	This information element indicates the context for the command.
		Bearer Termination	M	This information element indicates the bearer termination(s) for the command.
		Reason	M	This information element indicates the reason for service change.
		Method	M	This information element indicates the method for service change.
Termination Restoration Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Termination Restoration Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.36 Audit Value

This procedure is used to audit values of different object(s).

Table 16.37: Procedures between (G)MSC server and MGW: Audit Value

Procedure	Initiated	Information element name	Information element required	Information element description
Audit Value	(G)MSC-S	Context	M	This information element indicates the context for the command.
		Bearer Termination	M	This information element indicates the bearer termination(s) for the command.
		Object(s)	M	This information element indicates the object(s) to be audited.
Audit Value Ack	MGW	Context	M	This information element indicates the context where the command was executed.
		Bearer Termination	M	This information element indicates the bearer termination where the command was executed.
		Value(s)	M	This information element indicates the value(s) of the object(s).

16.2.37 Audit Capability

This procedure is used to audit capabilities of different object(s).

Table 16.38: Procedures between (G)MSC server and MGW: Audit Capability

Procedure	Initiated	Information element name	Information element required	Information element description
Audit Capability	(G)MSC-S	Context	M	This information element indicates the context for the command.
		Bearer Termination	M	This information element indicates the bearer termination(s) for the command.
		Object(s)	M	This information element indicates the object(s) which capability is requested.
Audit Capability Ack	MGW	Context	M	This information element indicates the context where the command was executed.
		Bearer Termination	M	This information element indicates the bearer termination where the command was executed.
		Capabilities(s)	M	This information element indicates the capabilities of the object(s).

16.2.38 Capability Update

This procedure is used to indicate update of an object capability.

Table 16.39: Procedures between (G)MSC server and MGW: Capability Update

Procedure	Initiated	Information element name	Information element required	Information element description
Capability Update	MGW	Context	M	This information element indicates the context for the command.
		Bearer Termination	M	This information element indicates the bearer termination(s) for the command.
		Reason	M	This information element indicates the reason for service change.
		Method	M	This information element indicates the method for service change.
Capability Update Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Capability Update Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.39 Command Reject

This command is used to reject the received command request. It may be used as response to any of the above procedures.

Table 16.40: Procedures between (G)MSC server and MGW: Command Reject

Procedure	Initiated	Information element name	Information element required	Information element description
Command Reject	Both	Context	M	This information element indicates the context where the command was rejected.
		Bearer Termination	M	This information element indicates the bearer termination where the command was rejected.
		Error	M	This information element indicates the error that caused command rejection.

16.2.40 Activate Voice Processing Function

This procedure is used to activate the voice processing (echo cancellation) function.

Table 16.41: Procedures between (G)MSC server and MGW: Activate Voice Processing Function

Procedure	Initiated	Information element name	Information element required	Information element description
Activate Voice Processing Function	(G)MSC-S	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the voice processing function is activated.
		Activate Voice Processing Function	M	This information element requests to activate the voice processing function.
Activate Voice Processing Function Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Activate Voice Processing Function Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.41 Modify Bearer Characteristics

This procedure is used to modify the bearer characteristics.

Table 16.42: Procedures between (G)MSC server and MGW: Modify Bearer Characteristics

Procedure	Initiated	Information element name	Information element required	Information element description
Modify Bearer Characteristics	(G)MSC-S	Context	M	This information element indicates the existing context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination for the bearer to be modified.
		Bearer Service Characteristics	C	This information element indicates the bearer service requested by the user. This information element is not included if the Codec information element is provided. It may be included for a data call (see 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6]).
		Circuit Switched Data	C	This information element indicates the PLMN bearer capabilities and when applicable GSM channel coding and user bit rate. This information element shall be included according to 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6] for a non-speech call by the MSC server, or by the anchor-MSC in case of inter-MSC handover, for UMTS radio access network side bearer termination and for network side bearer termination.
		Codec	C	This information element indicates the speech or multimedia coding format to be used for the bearer. This information element is included for the speech call and may be included for a SCUDIF multimedia call (see3GPP TS 23.172 [38], 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6])., for UMTS radio access network side bearer termination and for network side bearer termination.
		Framing Protocol	O	This information element indicates the framing protocol to be used for the bearer.
Modify Bearer Characteristics Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Modify Bearer Characteristics Ack	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.42 Protocol Negotiation Result

This procedure is used to inform the MSC about protocol negotiation result.

Table 16.43: Procedures between MSC server and MGW: Protocol Negotiation Result

Procedure	Initiated	Information element name	Information element required	Information element description
IWF Protocol Indication	MGW	Context	M	This information element indicates the existing context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination for the bearer to be modified.
		Protocol Negotiation result	M	This information element indicates the IWF protocol negotiation result
IWF Protocol Indication Ack	MSC	Context	M	This information element indicates the context where the command was executed.
IWF Protocol Indication Ack	MSC	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.43 MGW Resource Congestion Handling – Activate

This procedure is used to activate the congestion handling mechanism.

Table 16.44: Procedures between (G)MSC server and MGW: MGW Resource Congestion Handling – Activate

Procedure	Initiated	Information element name	Information element required	Information element description
MGW Resource Congestion Handling – Activate	(G)MSC-S	Context	M	This information element indicates that all context are applicable for the root termination.
		Root Termination	M	This information element indicates that root termination is where the congestion mechanism is activated.
		Congestion Activate	M	This information element requests to activate the congestion mechanism.
MGW Resource Congestion Handling – Activate Ack	MGW	Context	M	This information element indicates that all context are where the command was executed.
MGW Resource Congestion Handling – Activate Ack	MGW	Root Termination	M	This information element indicates that root termination is where the command was executed.

16.2.44 MGW Resource Congestion Handling – Indication

This procedure is used to inform the (G)MSC server that traffic restriction is advised.

Table 16.45: Procedures between (G)MSC server and MGW: MGW Resource Congestion Handling – Indication

Procedure	Initiated	Information element name	Information element required	Information element description
MGW Resource Congestion Handling – Indication	MGW	Context	M	This information element indicates all context are applicable for the root termination.
		Root Termination	M	This information element indicates that root termination is where the congestion mechanism was activated.
		Reduction	M	This information element indicates the load percentage to be reduced.
MGW Resource Congestion Handling – Indication Ack	(G)MSC	Context	M	This information element indicates all context are where the command was executed.
MGW Resource Congestion Handling – Indication Ack	(G)MSC	Root Termination	M	This information element indicates that root termination is where the command was executed.

16.2.45 Bearer Modification Support

This procedure is used to notify that the established bearer can be modified.

Table 16.46: Procedures between (G)MSC server and MGW: Bearer Modification

Procedure	Initiated	Information element name	Information element required	Information element description
Bearer Modification Support	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the bearer was established.
		Bearer Modification	M	This information element notifies that the established bearer can be modified.
Bearer Modification Support Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Bearer Modification Support Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.46 CTM report

This procedure is used to notify the outcome of the CTM negotiation in the user plane.

Table 16.47: Procedures between (G)MSC server and MGW: CTM report

Procedure	Initiated	Information element name	Information element required	Information element description
CTM report	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the CTM function was activated
		Outcome of CTM negotiation	M	This information element indicates whether the CTM negotiation in user plane was successful or not.
CTM report Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
CTM report Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.47 Prepare_IP_Transport

This procedure is used to prepare for a bearer establishment when IuCS on IP is supported by the MSC.

Table 16.48: Procedures between (G)MSC server and MGW: Prepare_IP_Transport

Procedure	Initiated	Information element name	Information element required	Information element description
Prepare_IP_Transport (G)MSC-S		Context/Context Request	M	This information element indicates the existing context or requests a new context for the IP Access bearer termination.
		Bearer Termination Request	M	This information element requests a new bearer termination for the IP Access bearer to be established.
		Iu UDP Port Request	M	This information element requests the Iu UDP Port in the MGW
		IP Transport Address Request	M	This information element requests the IP address of the MGW.
		Bearer Characteristics/ Bearer Characteristics Requests	M	This information element indicates the preferred characteristics of the bearer connection or requests the MGW to select and provide the bearer characteristics.
		Bearer Service Characteristics	C	This information element indicates the bearer service requested by the user. This information element is not included if the Codec information element is provided. It may be included for a data call (see 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6]).
		Notify Bearer Event	O	This information element requests a notification of an established bearer, a released bearer, a modified bearer or a bearer modification failure.
		Circuit Switched Data	C	This information element indicates the PLMN bearer capabilities and when applicable the user bit rate. This information element shall be included according to 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6] for a non-speech call by the MSC server, or by the anchor-MSC in case of inter-MSC handover, for a UMTS radio access network side bearer termination.
		Codec	C	This information element indicates the speech or multimedia coding format to be used for the bearer. This information element is included for a speech call and may be included for a SCUDIF multimedia call (see3GPP TS 23.172 [38], 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6]), for a UMTS radio access network side bearer termination.
		Framing Protocol	O	This information element indicates the framing protocol to be used for the bearer.
		Cellular Text telephony modem	C	This information element indicates the need of CTM function.
		IP Realm Identifier	O	This information element indicates the IP realm of the IP termination.
		Notify termination heartbeat	M	This information element requests termination heartbeat indications.
Prepare IP Transport Ack	MGW	Context	M	This information element indicates the context where the command was executed.
		Bearer Termination	M	This information element indicates the bearer termination where the command was executed.
		IP Transport Address	M	This information element indicates the IP address of the MGW
		Iu UDP Port	M	This information element requests the Iu UDP Port in the MGW

16.2.48 Modify IP Transport Address

This procedure is used when IuCS on IP is supported by the MGW and IuUP in transparent mode is configured.

Table 16.49: Procedures between (G)MSC server and MGW: RNC IP address notification

Procedure	Initiated	Information element name	Information element required	Information element description
Modify IP Transport Address	MSC-S	Context	M	This information element indicates the context for the IP bearer termination.
		Bearer Termination	M	This information element indicates the IP bearer termination where the RNC IP Address is needed.
		IP Transport address	M	This information element indicates the IP address of the RNC
		Iu UDP Port	M	This information element indicates the Iu UDP Port in the RNC
Modify IP Address Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Modify IP Address Ack	MGW	Bearer Termination	M	This information element indicates the IP bearer termination where the command is executed.

16.2.49 Emergency Call Indication

This procedure is used to indicate that the call is an emergency call.

Table 16.50: Procedures between (G)MSC server and MGW: Emergency Call Indication

Procedure	Initiated	Information element name	Information element required	Information element description
Emergency Call Indication	(G)MSC-S	Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
Emergency Call Indication	(G)MSC-S	Emergency Call Indicator	M	This information element indicates the emergency call information
Emergency Call Indication Ack	MGW	Context	M	This information element indicates the context where the command was executed.

16.2.50 Trace Activation

This procedure is used for activation of a Trace Session in a MGW.

Table 16.51: Procedures between (G)MSC server and MGW: Trace Activation

Procedure	Initiated	Information element name	Information element required	Information element description
Trace Activation	MSC-S	Context	M	This information element indicates the context for the command.
		Bearer Termination	M	This information element indicates the bearer termination(s) for the command.
		Trace Reference	C	Defined in 3GPP TS 32.421 and 3GPP TS 32.422
		Trace Session Recording Reference	C	Defined in 3GPP TS 32.421 and 3GPP TS 32.422
		Triggering Events	C	Defined in 3GPP TS 32.421 and 3GPP TS 32.422
		Trace Depth	C	Defined in 3GPP TS 32.421 and 3GPP TS 32.422
		List of interfaces	O	Defined 3GPP TS 32.422
		Trace Activity Control	M	This information element indicates the trace activation)
		IMSI	C	This information element shows the IMSI of the traced subscriber. Either IMSI or IMEI(SV) must be provided.
		IMEI(SV)	C	This information element shows the IMEI(SV) of the traced equipment. Either IMSI or IMEI(SV) must be provided.
		Notify Trace Activation result	O	This information element requests a notification of the result of the trace activation.
Trace Activation Reply	MGW	Context	M	This information element indicates the context where the command was executed.
Trace Activation Reply	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.51 Trace Deactivation

This procedure is used for deactivation of a Trace Session in a MGW..

Table 16.52: Procedures between (G)MSC server and MGW: Trace Deactivation

Procedure	Initiated	Information element name	Information element required	Information element description
Trace Deactivation	MSC-S	Context	M	This information element indicates the context for the command.
		Bearer Termination	M	This information element indicates the bearer termination(s) for the command.
		Trace Reference	M	Defined in 3GPP TS 32.421 and 3GPP TS 32.422
		Trace Activity Control	M	This information element indicates the trace deactivation
Trace Deactivation Reply	MGW	Context	M	This information element indicates the context where the command was executed.
Trace Deactivation Reply	MGW	Bearer Termination	M	This information element indicates the bearer termination where the command was executed

16.2.52 Trace Activation result notification

This procedure is used for informing the MSC Server about the result of the Trace Session Activation.

Table 16.53: Procedures between MGW and (G)MSC Server: Trace Activation result notification

Procedure	Initiated	Information element name	Information element required	Information element description
Trace Activation result notification	MGW	Context	M	This information element indicates the context for the command
		Bearer Termination	M	This information element indicates the bearer termination(s) for the command
		Result	M	This information element defines the result of the Trace Session Activation
Trace Activation result notification Ack	MSC-S	Context	M	This information element indicates the context where the command was executed
Trace Activation result notification Ack	MSC-S	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.53 Continuity Check Tone

This procedure is used by the (G)MSC to order the MGW to generate a continuity check tone at a TDM termination and to inform the (G)MSC about the result of the continuity check as soon as the continuity check tone is received or a time-out occurs.

Table 16.54: Continuity Check Tone procedure

Procedure	Initiated	Information element name	Information element required	Information element description
Continuity Check Tone	(G)MSC	Context/Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
		TDM Termination	M	This information element indicates the bearer termination
		Request for continuity tone sending	M	This information request the MGW to apply the continuity check procedure on the indicated TDM termination
		Request for continuity check tone detection	M	This information request the MGW to inform of result of the continuity check procedure on the indicated TDM termination
Continuity Check Tone Ack	IMGW	Context	M	This information element indicates the context where the command was executed.

16.2.54 Continuity Check Verify

This procedure is used by the MGW to indicate towards the (G)MSC that the continuity check at a TDM termination has been completed and to return the result of the check: success or failure.

Table 16.55: Continuity Check Verify procedure

Procedure	Initiated	Information element name	Information element required	Information element description
Continuity check Verify	MGW	Context/t	M	This information element indicates the context where the command was executed.
		TDM Termination	M	This information element indicates the TDM termination involved in the procedure
		Outcome of the continuity check	M	This information element indicates the outcome of the continuity check (successful/unsuccessful)
Continuity Check Verify Ack	(G)MSC	Context	M	This information element indicates the context where the command was executed.

16.2.55 Continuity Check Response

This procedure is used by the (G)MSC to order the MGW to loop back an incoming continuity check tone at a TDM termination.

Table 16.56: Continuity Check Response procedure

Procedure	Initiated	Information element name	Information element required	Information element description
Continuity Check Response	(G)MSC	Context/Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
		TDM Termination	M	This information element indicates the bearer termination
		Request for loop back of the continuity tone	M	This information request the MGW to loop back the continuity check tone on the indicated TDM termination
Continuity Check Response Ack	IMGW	Context	M	This information element indicates the context where the command was executed.

16.2.56 Rate Change

This procedure is used to notify that the CS data rate should be changed.

Table 16.57: Procedures between (G)MSC server and MGW: Rate Change

Procedure	Initiated	Information element name	Information element required	Information element description
Rate Change	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the rate change is required.
		Rate	M	This information element notifies the current rate.
Rate Change Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Rate Change Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.57 Bearer Modifed

This procedure is used to notify the modified bearer.

Table 16.2.57/1: Procedures between (G)MSC server and MGW: Bearer Modified

Procedure	Initiated	Information element name	Information element required	Information element description
Bearer Modified	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the bearer was modified.
		Bearer Modified	M	This information element notifies a bearer modification.
Bearer Modified Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Bearer Modified Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.58 Bearer Modification Failed

This procedure is used to notify the failed bearer modification.

Table 16.2.58/1: Procedures between (G)MSC server and MGW: Bearer Modification failed

Procedure	Initiated	Information element name	Information element required	Information element description
Bearer Modification Failed	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the bearer modification failed.
		Bearer Modification failure	M	This information element notifies a bearer modification failure
Bearer Modification Failed Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Bearer Modification Failed Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.

16.2.59 Termination heartbeat indication

This procedure is used to report indication of hanging termination.

Table 16.2.59/1: Procedures between (G)MSC server and MGW: Hanging termination indication

Procedure	Initiated	Information element name	Information element required	Information element description
Termination heartbeat indication	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination for which the termination heartbeat is reported.
		Termination heartbeat	M	Hanging termination event as defined in 3GPP TS 29.232 [6].
Termination heartbeat indication Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Termination heartbeat indication Ack	(G)MSC-S	Bearer Termination	M	This information element indicates the Bearer Termination where the command was executed.

16.2.60 Inactivity timeout activation

This procedure is used to activate the inactivity timeout mechanism.

Table 16.2.60/1: Procedures between (G)MSC server and MGW: Inactivity timeout activation

Procedure	Initiated	Information element name	Information element required	Information element description
Inactivity timeout activation	(G)MSC-S	Context	M	This information element indicates the context for the command.
		Root Termination	M	This information element indicates that root termination is where the inactivity timeout mechanism is activated.
		Inactivity Timeout	M	Inactivity timeout event as defined in 3GPP TS 29.232 [6].
Inactivity timeout activation Ack	MGW	Context	M	This information element indicates the context where the command was executed.
Inactivity timeout activation Ack	MGW	Root Termination	M	This information element indicates that root termination is where the command was executed.

16.2.61 Inactivity timeout indication

This procedure is used by MGW to report indication of inactivity timeout to MGC.

Table 16.2.61/1: Procedures between (G)MSC server and MGW: Inactivity timeout indication

Procedure	Initiated	Information element name	Information element required	Information element description
Inactivity timeout indication	MGW	Context	M	This information element indicates the context for the command.
		ROOT Termination	M	This information element indicates that root termination is where the inactivity timeout mechanism was activated.
		Inactivity Timeout	M	Inactivity timeout event as defined in 3GPP TS 29.232 [6].
Inactivity timeout indication Ack	(G)MSC-S	Context	M	This information element indicates the context where the command was executed.
Inactivity timeout indication Ack	(G)MSC-S	ROOT Termination	M	This information element indicates that root termination is where the command was executed.

16.2.62 Reserve RTP Connection Point

This procedure is used to reserve an RTP bearer termination.

Table 16.2.62.1: Reserve RTP Connection Point

Procedure	Initiated	Information element name	Information element required	Information element description
Reserve RTP Connection Point	(G)MSC-Server	Context/Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
		Termination Request	M	This information element requests a new termination for the bearer to be established.
		IP Interface	O	This information element specifies the type of external interface to be used for the IP termination (e.g. AoIP).
		Local IP Resources	M	This information element indicates the resource(s) (e.g. codec, auxiliary payload types) for which the MGW shall be prepared to receive user data,
		ReserveValue	C	This information element indicates if multiple local resources are to be reserved. This information element shall be included if a speech codec and auxiliary payload types are required.
		Local Connection Address Request	M	This information element requests an IP address and port number on the MGW that the remote end can send user plane data to.
		Notify termination heartbeat	M	This information element requests termination heartbeat indications.
		Notify Released Bearer	O	This information element requests a notification of a released bearer.
		IP Realm Identifier	O	This information element indicates the IP realm of the IP termination.
		Cellular Text telephony modem	C	This information element indicates the need of CTM function. (NOTE 1)
		Number of desired listener context terminations	O	This information element indicates the number of desired terminations for a listener context in a VGCS or VBS call. It should be included in the first ADD request which establishes a Listener context. (NOTE 1)
		Circuit Switched Data	C	This information element indicates the PLMN bearer capabilities and when applicable GSM channel coding. This information element shall be included according to 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6] for a non-speech / non SCUDIF multimedia call (see 3GPP TS 23.172 [20]) by the MSC server, or by the anchor-MSC in case of inter-MSC handover, for an anchor MGW network termination.
		IP Version	C	This information element indicates the version of the internet protocol to be applied at the termination for the user plane. This is required for IP address translation. (NOTE 4)
		DiffServ Code Point	O	This information element indicates a specific DiffServ code point to be used in the IP header in packets sent on the IP termination. (NOTE 4)
		DiffServ Tagging Behaviour	O	This information element indicates whether the Diffserv code point in the IP header in packets sent on the IP termination should be copied from the received value or set to a specific value. (NOTE 4)
		Remote Source Address Filtering	O	This information element indicates that remote source address filtering is required. (NOTE 4)
		Remote Source Address Mask	C	This information element provides information on the valid remote source addresses. This may be included if remote source address filtering is included. It shall not be included if remote source address filtering is not included. (NOTE 4)
		Remote Source Port Filtering	O	This information element indicates that remote source port filtering is required. (NOTE 4)
		Remote Source Port	C	This information element identifies the valid remote source port. This may be included if remote source port filtering is included. It shall not be included if remote source port filtering is not included. (NOTE 2, NOTE 4)
		Remote Source Port Range	C	This information element identifies a range of valid remote source ports. This may be included if remote source port filtering is included. It shall not be included if remote source port filtering is not included. (NOTE 2, NOTE 4)
		Media Inactivity Detection Required	O	This information element indicates that detection of inactive media flows is required. (NOTE 4)
		Inactivity Detection Time	C	This information element may be present if Inactive Media Detection is required and specifies the Inactivity Detection time. (NOTE 4)
		Inactivity Detection Direction	C	This information element may be present if Inactive Media Detection is required and specifies the Inactivity Detection direction. (NOTE 4)
		RTCP handling	O	Indicates whether or not the CS-MGW shall reserve a port for an RTCP flow. (NOTE 4)
		Traffic Policing Required	O	This information element indicates that policing of the media flow is required. (NOTE 4)
		Peak Data Rate	O	This information element may be present if Policing is required and specifies the permissible peak data rate for a media stream. (NOTE 3, NOTE 4)
		Sustainable Data Rate	O	This information element may be present if Policing is required and specifies the permissible sustainable data rate for a media stream. (NOTE 3, NOTE 4)
		Delay Variation Tolerance	O	This information element may be present if Policing on Peak Data Rate is required and specifies the maximum expected delay variation tolerance for the corresponding media stream. (NOTE 4)
		Maximum Burst Size	C	This information element shall be present if Policing on Sustainable Data Rate is required and specifies the maximum expected burst size for the corresponding media stream. (NOTE 4)
Reserve RTP Connection Point Ack	MGW	Context	M	This information element indicates the context where the command was executed.
		Termination	M	This information element indicates the termination where the command was executed.
		Local IP Resources	M	This information element indicates the resources that the MGW has reserved to receive the user plane data from the remote peer.
		Local Connection Address	M	This information element indicates the IP address and port on the MGW that shall receive user plane data from the remote peer.
NOTE 1: Only applies for Access side terminations NOTE 2: Remote Source Port and Remote Source Port Range are mutually exclusive. NOTE 3: At least one of these IEs shall be present when policing is required. NOTE 4: This information element is used for border control functions as defined in Annex A of 3GPP TS 29.235 [44]

16.2.63 Configure RTP Connection Point

This procedure is used to configure or reconfigure an RTP bearer termination.

Table 16.2.63.1: Configure RTP Connection Point Procedure

Procedure	Initiated	Information element name	Information element required	Information element description
Configure RTP Connection Point	(G)MSC-Server	Context	M	This information element indicates the existing context.
		Termination	M	This information element indicates the existing bearer termination.
		IP Interface	O	This information element specifies the type of external interface to be used for the IP termination (e.g. AoIP).
		Local IP Resources	O	This information element indicates the resources (e.g. codec, auxiliary payload types) that the MGW may use on the reception of user plane data.
		Remote IP Resources	O	This information element indicates the resources (e.g. codec, auxiliary payload types) that the MGW may send user plane data to.
		Local Connection Address	O	This information element indicates the IP address and port on the MGW that the remote peer can send user plane data to.
		Remote Connection Address	O	This information element indicates the IP address and port that the MGW can send user plane data to.
		Reserve Value	C	This information element indicates if multiple resources are to be reserved. This information element shall be included if a speech codec and auxiliary payload types are required.
		Cellular Text telephony modem	C	This information element indicates the need of CTM function. (NOTE 1)
		Number of desired listener context terminations	O	This information element indicates the number of desired terminations for a listener context in a VGCS or VBS call. It should be included in the first ADD request which establishes a Listener context. (NOTE 1)
		Circuit Switched Data	O	This information element indicates the PLMN bearer capabilities and when applicable GSM channel coding. This information element shall be included according to 3GPP TS 29.007 [37] and 3GPP TS 29.232 [6] for a non-speech/ non SCUDIF multimedia call by the MSC server, or by the anchor-MSC in case of inter-MSC handover for an anchor MGW network termination.
		DiffServ Code Point	O	This information element indicates a specific DiffServ code point to be used in the IP header in packets sent on the IP termination. (NOTE 4)
		DiffServ Tagging Behaviour	O	This information element indicates whether the Diffserv code point in the IP header in packets sent on the IP termination should be copied from the received value or set to a specific value. (NOTE 4)
		Remote Source Address Filtering	O	This information element indicates that remote source address filtering is required. (NOTE 4)
		Remote Source Address Mask	C	This information element provides information on the valid remote source addresses. This may be included if remote source address filtering is included. It shall not be included if remote source address filtering is not included. (NOTE 4)
		Remote Source Port Filtering	O	This information element indicates that remote source port filtering is required. (NOTE 4)
		Remote Source Port	C	This information element identifies the valid remote source port. This may be included if remote source port filtering is included. It shall not be included if remote source port filtering is not included. (NOTE 2, NOTE 4)
		Remote Source Port Range	C	This information element identifies a range of valid remote source ports. This may be included if remote source port filtering is included. It shall not be included if remote source port filtering is not included. (NOTE 2, NOTE 4)
		Media Inactivity Detection Required	O	This information element indicates that detection of inactive media flows is required. (NOTE 4)
		Inactivity Detection Time	C	This information element may be present if Inactive Media Detection is required and specifies the Inactivity Detection time. (NOTE 4)
		Inactivity Detection Direction	C	This information element may be present if Inactive Media Detection is required and specifies the Inactivity Detection direction. (NOTE 4)
		RTCP handling	O	Indicates whether or not the CS-MGW shall reserve a port for an RTCP flow. (NOTE 4)
		Traffic Policing Required	O	This information element indicates that policing of the media flow is required. (NOTE 4)
		Peak Data Rate	O	This information element may be present if Policing is required and specifies the permissible peak data rate for a media stream.(NOTE 3, NOTE 4)
		Sustainable Data Rate	O	This information element may be present if Policing is required and specifies the permissible sustainable data rate for a media stream.(NOTE 3, NOTE 4)
		Delay Variation Tolerance	O	This information element may be present if Policing on Peak Data Rate is required and specifies the maximum expected delay variation tolerance for the corresponding media stream. (NOTE 4)
		Maximum Burst Size	C	This information element shall be present if Policing on Sustainable Data Rate is required and specifies the maximum expected burst size for the corresponding media stream. (NOTE 4)
Configure RTP Connection Point Ack	MGW	Context	M	This information element indicates the context where the command was executed.
		Termination	M	This information element indicates the termination where the command was executed.
		Local IP Resource	O	This information element indicates the resources that the MGW has reserved to receive the user plane data from the far end.
		Remote IP Resource	C	This information element indicates the resource (i.e. codec) that the MGW shall use to send user data to. Shall be present if corresponding IE is present in the request.
		Local Connection Address	O	This information element indicates the IP address and port on the MGW that the remote end can send user plane data to.
		Remote Connection Address	C	This information element indicates the IP address and port that the MGW can send user plane data to. Shall be present if corresponding IE is present in the request.
NOTE 1: Only applies for Access side terminations NOTE 2: Remote Source Port and Remote Source Port Range are mutually exclusive. NOTE 3: At least one of these IEs shall be present when policing is required. NOTE 4: This information element is used for border control functions as defined in Annex A of 3GPP TS 29.235 [44]

16.2.64 Reserve and Configure RTP Connection Point

This procedure is used to reserve and configure multimedia-processing resources for an RTP termination.

Table 16.2.64.1: Reserve and Configure RTP Connection Point

Procedure	Initiated	Information element name	Information element required	Information element description
Reserve and Configure RTP Connection Point	(G)MSC-Server	Context/Context Request	M	This information element indicates the existing context or requests a new context for the bearer termination.
		Termination/ Termination Request	M	This information element indicates the existing bearer termination or requests a new termination for the bearer to be established.
		IP Interface	O	This information element specifies the used interface type for the IP termination (e.g. NboIP).
		Local IP Resources	M	This information element indicates the resource(s) (e.g. codec, auxiliary payload types) for which the MGW shall be prepared to receive user data,
		Remote IP Resources	M	This information element indicates the resources (e.g. codec, auxiliary payload types) that the MGW shall use to send user data.
		Reserve Value	C	This information element indicates if multiple IP resources are to be reserved. This information element shall be included if a speech codec and auxiliary payload types are required.
		Cellular Text telephony modem	C	This information element indicates the need of CTM function. (NOTE 1)
		Local Connection Address Request	M	This information element requests an IP address and port number on the MGW that the remote end can send user plane data to.
		Remote Connection Address	M	This information element indicates the IP address and ports of the remote party that the MGW can send user plane data to.
		Notify termination heartbeat	M	This information element requests termination heartbeat indications.
		Notify Released Bearer	O	This information element requests a notification of a released bearer.
		IP Realm Identifier	O	This information element indicates the IP realm of the IP termination.
		Circuit Switched Data	O	This information element indicates the PLMN bearer capabilities and when applicable GSM channel coding. This information element shall be included according to 3GPP TS 29.007 [6] and 3GPP TS 29.232 [8] for a non-speech / non SCUDIF multimedia call (see 3GPP TS 23.172 [20]) by the MSC server, or by the anchor-MSC in case of inter-MSC handover, for an anchor MGW network termination.
		IP Version	C	This information element indicates the version of the internet protocol to be applied at the termination for the user plane. This is required for IP address translation. (NOTE 4)
		DiffServ Code Point	O	This information element indicates a specific DiffServ code point to be used in the IP header in packets sent on the IP termination. (NOTE 4)
		DiffServ Tagging Behaviour	O	This information element indicates whether the Diffserv code point in the IP header in packets sent on the IP termination should be copied from the received value or set to a specific value. (NOTE 4)
		Remote Source Address Filtering	O	This information element indicates that remote source address filtering is required. (NOTE 4)
		Remote Source Address Mask	C	This information element provides information on the valid remote source addresses. This may be included if remote source address filtering is included. It shall not be included if remote source address filtering is not included. (NOTE 4)
		Remote Source Port Filtering	O	This information element indicates that remote source port filtering is required. (NOTE 4)
		Remote Source Port	C	This information element identifies the valid remote source port. This may be included if remote source port filtering is included. It shall not be included if remote source port filtering is not included. (NOTE 2, NOTE 4)
		Remote Source Port Range	C	This information element identifies a range of valid remote source ports. This may be included if remote source port filtering is included. It shall not be included if remote source port filtering is not included. (NOTE 2, NOTE 4)
		Media Inactivity Detection Required	O	This information element indicates that detection of inactive media flows is required. (NOTE 4)
		Inactivity Detection Time	C	This information element may be present if Inactive Media Detection is required and specifies the Inactivity Detection time. (NOTE 4)
		Inactivity Detection Direction	C	This information element may be present if Inactive Media Detection is required and specifies the Inactivity Detection direction. (NOTE 4)
		RTCP handling	O	Indicates whether or not the CS-MGW shall reserve a port for an RTCP flow. (NOTE 4)
		Traffic Policing Required	O	This information element indicates that policing of the media flow is required. (NOTE 4)
		Peak Data Rate	O	This information element may be present if Policing is required and specifies the permissible peak data rate for a media stream.(NOTE 3, NOTE 4)
		Sustainable Data Rate	O	This information element may be present if Policing is required and specifies the permissible sustainable data rate for a media stream.(NOTE 3, NOTE 4)
		Delay Variation Tolerance	O	This information element may be present if Policing on Peak Data Rate is required and specifies the maximum expected delay variation tolerance for the corresponding media stream. (NOTE 4)
		Maximum Burst Size	C	This information element shall be present if Policing on Sustainable Data Rate is required and specifies the maximum expected burst size for the corresponding media stream. (NOTE 4)
Reserve and Configure RTP Connection Point	MGW	Context	M	This information element indicates the context where the command was executed.
		Termination	M	This information element indicates the termination where the command was executed.
		Local IP Resources	M	This information element indicates the resources that the MGW has reserved to receive the user plane data from the remote side.
		Remote IP Resources	M	This information element indicates the resource (i.e. codec) that the MGW shall use to send user data.
		Local Connection Addresses	M	This information element indicates the IP address and port on the MGW that shall receive user plane data.
NOTE 1: Only applies for Access side terminations NOTE 2: Remote Source Port and Remote Source Port Range are mutually exclusive. NOTE 3: At least one of these IEs shall be present when policing is required. NOTE 4: This information element is used for border control functions as defined in Annex A of 3GPP TS 29.235 [44]

16.2.65 Realm Availability Change – Activation

This procedure is used to activate the realm availability notification mechanism.

Table 16.2.65.1: Realm Availability Change – Activation

Procedure	Initiated	Information element name	Information element required	Information element description
Realm Availability Change – Activate	(G)MSC-Server	Context	M	This information element indicates the NULL context.
		Root Termination	M	This information element indicates that root termination is where the realm availability change notification mechanism is activated.
		Realm Availability Change Activate	M	This information element requests to activate the realm availability change notification mechanism.
Realm Availability Change -Activate Ack	MGW	Context	M	This information element indicates the NULL context.
Realm Availability Change -Activate Ack	MGW	Root Termination	M	This information element indicates that root termination is where the command was executed.
NOTE: This procedure is used for border control functions as defined in Annex A of 3GPP TS 29.235 [44]

16.2.66 Realm Availability Change – Indication

This procedure is used to inform the (G)MSC-Server that there has been a change to the list of currently available realms.

Table 16.2.66.1: Realm Availability Change – Indication

Procedure	Initiated	Information element name	Information element required	Information element description
Realm Availability Change – Indication	MGW	Context	M	This information element indicates the NULL context.
		Root Termination	M	This information element indicates that root termination is where the realm availability change notification mechanism was activated.
		Changes to Realm Availability	M	This information element indicates the changes to the list of available realms.
Realm Availability Change – Indication Ack	(G)MSC-Server	Context	M	This information element indicates the NULL context.
Realm Availability Change – Indication Ack	(G)MSC-Server	Root Termination	M	This information element indicates that root termination is where the command was executed.
NOTE: This procedure is used for border control functions as defined in Annex A of 3GPP TS 29.235 [44]

16.2.67 Media Inactivity Notification

This procedure is used to notify the (G)MSC-Server of media inactivity on the MGW.

Table 16.2.67.1: Media Inactivity Notification

Procedure	Initiated	Information element name	Information element required	Information element description
Media Inactivity Notification	MGW	Context	M	This information element indicates the context for the bearer termination.
		Bearer Termination	M	This information element indicates the bearer termination where the media inactivity detection was activated.
		Media Inactivity	M	This information element notifies the (G)MSC-Server of Media inactivity detection on the bearer termination.
Media Inactivity Notification Ack	(G)MSC-Server	Context	M	This information element indicates the context where the command was executed.
Media Inactivity Notification Ack	(G)MSC-Server	Bearer Termination	M	This information element indicates the bearer termination where the command was executed.
NOTE: This procedure is used for border control functions as defined in Annex A of 3GPP TS 29.235 [44]