17 Message functional definitions and contents

09.183GPPGeneral Packet Radio Service (GPRS)Gs interface layer 3 specificationServing GPRS Support Node (SGSN) - Visitors Location Register (VLR)TS

This section defines the structure of the messages that are sent between the SGSN and the VLR.

17.1 Message Contents

17.1.1 BSSAP+-ALERT-ACK message

This message is sent by the SGSN to the VLR to acknowledge a previous BSSAP+-ALERT-REQUEST message.

Table 17.1.1/3GPP TS 09.18: BSSAP+-ALERT-ACK message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10

17.1.2 BSSAP+-ALERT-REJECT message

This message is sent from the SGSN to the VLR to indicate that the SGSN could not identify the IMSI indicated in the BSSAP+-ALERT-Request message.

Table 17.1.2/3GPP TS 09.18: BSSAP+-ALERT-REJECT message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
Gs Cause	Gs Cause 18.4.6	M	TLV	3

17.1.2.1 Gs Cause

The value part which is typically sent for this information element in this message is ‘IMSI unknown’.

17.1.3 BSSAP+-ALERT-REQUEST message

This message is sent by the VLR to the SGSN to request an indication when next activity from the MS is detected.

Table 17.1.3/3GPP TS 09.18: BSSAP+-ALERT-REQUEST message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10

17.1.4 BSSAP+-GPRS-DETACH-ACK message

This message is sent by the VLR to the SGSN to acknowledge a previous BSSAP+-GPRS-DETACH-Indication message. The type of detach acknowledged is indicated in the GPRS detach type IE.

Table 17.1.4/3GPP TS 09.18: BSSAP+-GPRS-DETACH-ACK message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10

17.1.5 BSSAP+-GPRS-DETACH-INDICATION message

This message is sent by the SGSN to the VLR to indicate a GPRS detach performed from the MS or the SGSN. The type of detach is indicated in the GPRS detach type IE.

Table 17.1.5/3GPP TS 09.18: BSSAP+-GPRS-DETACH-INDICATION message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
SGSN number	SGSN number 18.4.21	M	TLV	5-11
IMSI detach from GPRS service type	IMSI detach from GPRS service type 18.4.16	M	TLV	3
Cell global identity	Cell global identity 18.4.1	O	TLV	10

17.1.5.1 Cell global identity

The SGSN shall include the Cell global identity where the mobile was in the last radio contact.

17.1.6 BSSAP+-IMSI-DETACH-ACK message

This message is sent by the VLR to the SGSN to acknowledge a previous BSSAP+-IMSI-DETACH-Indication message. The type of detach acknowledged is indicated in the IMSI detach type IE.

Table 17.1.6/3GPP TS 09.18: BSSAP+-IMSI-DETACH-ACK message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10

17.1.7 BSSAP+-IMSI-DETACH-INDICATION message

This message is sent by the SGSN to the VLR to indicate an IMSI detach performed from the MS. The type of detach is indicated in the IMSI detach type IE.

Table 17.1.7/3GPP TS 09.18: BSSAP+-IMSI-DETACH-INDICATION message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
SGSN number	SGSN number 18.4.21	M	TLV	5-11
Detach type	IMSI detach from non-GPRS service type 18.4.11	M	TLV	3
Cell global identity	Cell global identity 18.4.1	O	TLV	10
Location information age	Location information age 18.4.14	O	TLV	4

17.1.7.1 Cell global identity

The SGSN shall include the Cell global identity where the mobile was in the last radio contact.

17.1.7.2 Location information age

If the detach is due to implicit detach and the Cell global identity is available, then the SGSN should include the Location information age.

17.1.8 BSSAP+-LOCATION-UPDATE-ACCEPT message

This message is sent by the VLR to the SGSN to indicate that update or IMSI attach in the VLR has been completed.

Table 17.1.8/3GPP TS 09.18: BSSAP+-LOCATION-UPDATE-ACCEPT message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
Location area identifier	Location area identifier 18.4.13	M	TLV	7
New TMSI, or IMSI	Mobile identity 18.4.16	O	TLV	6-10

17.1.8.1 New TMSI, or IMSI

This information element represents the identity to be used for (and then by) the MS.

If this information element is an IMSI, then the mobile station is not allocated any TMSI (and deletes any TMSI accordingly). If this information element is a TMSI, then the mobile station will use this TMSI as the new temporary identity (the MS deletes its old TMSI and stores the new TMSI). If neither a TMSI nor an IMSI are included in this information element, the old TMSI, if any available, will be kept.

17.1.9 BSSAP+-LOCATION-UPDATE-REJECT message

This message is sent by the VLR to the SGSN to indicate that location update or IMSI attach has failed.

Table 17.1.9/3GPP TS 09.18: BSSAP+-LOCATION-UPDATE-REJECT message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
Reject cause	Reject cause 18.4.20	M	TLV	3

17.1.10 BSSAP+-LOCATION-UPDATE-REQUEST message

This message is sent by the SGSN to the VLR either to request update of its location file (normal update) or to request IMSI attach.

Table 17.1.10/3GPP TS 09.18: BSSAP+-LOCATION-UPDATE-REQUEST message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
SGSN number	SGSN number 18.4.21	M	TLV	5-11
Update type	GPRS location update type 18.4.5	M	TLV	3
New Cell global identity	Cell global identity 18.4.1	M	TLV	10
Mobile station classmark	Moblie station classmark 1 18.4.17	M	TLV	3
Old location area identifier	Location area identifier 18.4.13	O	TLV	7
TMSI status	TMSI status 18.4.23	O	TLV	3

17.1.10.1 Old location area identifier

This information element should be included. It is derived from the old routing area identification received in the ROUTING AREA UPDATING REQUEST message defined in 3GPP TS 04.08.

17.1.10.2 New cell global identity

The cell global identity which shall be included is the one where the MS is in the current radio contact.

17.1.10.3 TMSI status

This information element shall be included if the TMSI status received in the ATTACH REQUEST or ROUTING AREA UPDATING REQUEST message from the MS indicates, that no valid TMSI is available in the MS.

17.1.11 BSSAP+-MM-INFORMATION-REQUEST

This message is sent by the VLR to the SGSN to provide the MS with subscriber specific information.

Table 17.1.11/3GPP TS 09.18: BSSAP+-MM-INFORMATION-REQUEST message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
MM information	MM information 18.4.15	O	TLV	3-n

17.1.11.1 MM information

This information element should be included in this message.

17.1.12 BSSAP+-MOBILE-STATUS message

This message is sent by both the SGSN or the VLR to indicate an error.

Table 17.1.12/3GPP TS 09.18: BSSAP+-MOBILE-STATUS message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	O	TLV	6-10
Gs Cause	Gs Cause 18.4.6	M	TLV	3
Erroneous message	Erroneous message 18.4.4	M	TLV	3-n

17.1.12.1 IMSI

If the MS is identified by the IMSI, then this information element shall be included.

17.1.13 BSSAP+-MS-ACTIVITY-INDICATION message

This message is sent by the SGSN to the VLR to indicate that activity from an MS has been detected.

Table 17.1.13/3GPP TS 09.18: BSSAP+-MS-ACTIVITY-INDICATION message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
Cell global identity	Cell global identity 18.4.1	O	TLV	10

17.1.13.1 Cell global identity

The SGSN shall include the cell global identity where the MS was in the last radio contact.

17.1.14 BSSAP+-MS-INFORMATION-REQUEST message

This message is sent from the VLR to the SGSN to request information associated with the indicated IMSI. The type of information requested is specified in the Information requested IE.

Table 17.1.14/3GPP TS 09.18: BSSAP+-MS-INFORMATION-REQUEST message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
Information requested	Information requested 18.4.12	M	TLV	3

17.1.15 BSSAP+-MS-INFORMATION-RESPONSE message

This message is sent from the SGSN to the VLR as a response to a previous BSSAP+- MS-INFORMATION -REQUEST message. (At least one of the requested identities shall be sent).

Table 17.1.15/3GPP TS 09.18: BSSAP+-MS-INFORMATION-RESPONSE message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
TMSI	TMSI 18.4.22	O	TLV	6
PTMSI	PTMSI 18.4.19	O	TLV	6
IMEI	IMEI 18.4.7	O	TLV	10
IMEISV	IMEISV 18.4.8	O	TLV	10
Cell global identity	Cell global identity 18.4.1	O	TLV	10
Location information age	Location information age 18.4.14	O	TLV	4
Mobile station state	Mobile station state 18.4.18	O	TLV	3

17.1.15.1 IMEI

This information element should be included if it was requested in the BSSAP+-MS-INFORMATION-REQUEST message and if this information is obtainable.

17.1.15.2 IMIESV

This information element should be included if it was requested in the BSSAP+-MS-INFORMATION-REQUEST message and if this information is obtainable.

17.1.15.3 Cell global identity

Cell global identity where the MS was in the last radio contact.

This information element should be included if it was requested in the BSSAP+-MS-INFORMATION-REQUEST message and if this information is obtainable.

17.1.15.4 Location information age

Time in minutes since the MS last established a radio transaction.

This information element should be included if it was requested in the BSSAP+-MS-INFORMATION-REQUEST message and if this information is obtainable.

17.1.15.5 Mobile station state

This information element should be included in this message, irrespective of the information requested.

17.1.15.6 TMSI

This information element should be included if it was requested in the BSSAP+-MS-INFORMATION-REQUEST message and if this information is obtainable.

17.1.16 BSSAP+-MS-UNREACHABLE message

This message is sent from the SGSN to the VLR to indicate that, for example, paging could not be performed because the MS is marked as unreachable at the SGSN.

Table 17.1.16/3GPP TS 09.18: BSSAP+-MS-UNREACHABLE message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
Gs Cause	Gs Cause 18.4.6	M	TLV	3

17.1.16.1 Gs Cause

The value part which is typically sent for this information element in this message is ‘MS unreachable’.

17.1.17 BSSAP+-PAGING-REJECT message

This message is sent from the SGSN to the VLR to indicate that the delivery of a previous BSSAP+-PAGING-REQUEST message has failed.

Table 17.1.17/3GPP TS 09.18: BSSAP+-PAGING-REJECT message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
Gs Cause	Gs Cause 18.4.6	M	TLV	3

17.1.18 BSSAP+-PAGING-REQUEST message

This message is sent from the VLR to the SGSN and contains sufficient information to allow the paging message to be transmitted by the correct cells at the correct time.

Table 17.1.18/3GPP TS 09.18: BSSAP+-PAGING_REQUEST message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
VLR number	VLR number 18.4.24	M	TLV	5-11
TMSI	TMSI 18.4.22	O	TLV	6
Location area identifier	Location area identifier 18.4.13	O	TLV	7
Channel needed	Channel needed 18.4.2	O	TLV	3
eMLPP Priority	eMLPP Priority 18.4.3	O	TLV	3

17.1.18.1 TMSI

This element is omitted in the exceptional case where the IMSI is used instead of the TMSI as a paging address at the radio interface.

17.1.18.2 Location area identifier

If the location area identifier is not included, then the SGSN shall page the MS in all the cells served by the VLR and the SGSN, unless the SGSN has reliable information about the location of the MS.

17.1.18.3 Channel needed

If the Channel needed Information Element is not present, then the default value is assumed to be “ any channel ”.

17.1.18.4 eMLPP priority

This information element may be included when the subscriber has a subscription for eMLPP.

17.1.19 BSSAP+-RESET-ACK message

This message is sent from the SGSN or the VLR to acknowledge a previous BSSAP+-RESET-INDICATION message. This message indicates that all the associations to the VLR or the SGSN have been be marked as invalid.

The sending entity (either SGSN or VLR) includes its identity in the BSSAP+-RESET-ACK message.

Table 16.16/3GPP TS 09.18: BSSAP+-RESET-ACK message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
SGSN number	SGSN number 18.4.21	C	TLV	5-11
VLR number	VLR number 18.4.24	C	TLV	5-11

17.1.19.1 SGSN number

If the SGSN is the sending entity, then it shall indicate its address by including its SGSN number Information Element. Otherwise (i.e. if the VLR is the sending entity), then the SGSN number Information Element shall not be included.

17.1.19.2 VLR number

If the VLR is the sending entity, then it shall indicate its address by including its VLR number Information Element. Otherwise (i.e. if the SGSN is the sending entity), then the VLR number Information Element shall not be included.

17.1.20 BSSAP+-RESET-INDICATION message

This message is sent from the VLR to the SGSN to indicate that a failure in the VLR has occurred and all the associations to the VLR shall be marked as invalid.

This message is also sent from the SGSN to the VLR to indicate that a failure in the SGSN has occurred and all the associations to the SGSN shall be marked as invalid.

The sending entity (either SGSN or VLR) includes its identity in the BSSAP+-RESET-INDICATION message.

Table 17.1.20/3GPP TS 09.18: BSSAP+-RESET-INDICATION message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
SGSN number	SGSN number 18.4.21	C	TLV	5-11
VLR number	VLR number 18.4.24	C	TLV	5-11

17.1.20.1 SGSN number

If the SGSN is the sending entity, then it shall indicate its address by including its SGSN number Information Element. Otherwise (i.e. if the VLR is the sending entity), then the SGSN number Information Element shall not be included.

17.1.20.2 VLR number

If the VLR is the sending entity, then it shall indicate its address by including its VLR number Information Element. Otherwise (i.e. if the SGSN is the sending entity), then the VLR number Information Element shall not be included.

17.1.21 BSSAP+-TMSI-REALLOCATION-COMPLETE message

This message is sent by the SGSN to the VLR to indicate that TMSI reallocation on the MS has been successfully completed.

Table 17.1.21/3GPP TS 09.18: BSSAP+-TMSI-REALLOCATION-COMPLETE message content

Information Element	Type/Reference	Presence	Format	Length
Message type	Message type 18.2	M	V	1
IMSI	IMSI 18.4.9	M	TLV	6-10
Cell global identity	Cell global identity 18.4.1	O	TLV	10

17.1.21.1 Cell global identity

The SGSN shall include the cell global identity where the Mobile Station was in the last radio contact.