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 | M | V | 1 |
IMSI | IMSI | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
Gs Cause | Gs Cause | 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 | M | V | 1 |
IMSI | IMSI | 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 | M | V | 1 |
IMSI | IMSI | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
SGSN number | SGSN number | M | TLV | 5-11 |
IMSI detach from GPRS service type | IMSI detach from GPRS service type | M | TLV | 3 |
Cell global identity | Cell global identity | 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 | M | V | 1 |
IMSI | IMSI | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
SGSN number | SGSN number | 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 | O | TLV | 10 |
Location information age | Location information age | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
Location area identifier | Location area identifier | M | TLV | 7 |
New TMSI, or IMSI | Mobile identity | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
Reject cause | Reject cause | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
SGSN number | SGSN number | M | TLV | 5-11 |
Update type | GPRS location update type | M | TLV | 3 |
New Cell global identity | Cell global identity | M | TLV | 10 |
Mobile station classmark | Moblie station classmark 1 | M | TLV | 3 |
Old location area identifier | Location area identifier | O | TLV | 7 |
TMSI status | TMSI status | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
MM information | MM information | 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 | M | V | 1 |
IMSI | IMSI | O | TLV | 6-10 |
Gs Cause | Gs Cause | M | TLV | 3 |
Erroneous message | Erroneous message | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
Cell global identity | Cell global identity | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
Information requested | Information requested | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
TMSI | TMSI 18.4.22 | O | TLV | 6 |
PTMSI | PTMSI 18.4.19 | O | TLV | 6 |
IMEI | IMEI | O | TLV | 10 |
IMEISV | IMEISV | O | TLV | 10 |
Cell global identity | Cell global identity | O | TLV | 10 |
Location information age | Location information age | O | TLV | 4 |
Mobile station state | Mobile station state | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
Gs Cause | Gs Cause | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
Gs Cause | Gs Cause | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
VLR number | VLR number | M | TLV | 5-11 |
TMSI | TMSI | O | TLV | 6 |
Location area identifier | Location area identifier | O | TLV | 7 |
Channel needed | Channel needed | O | TLV | 3 |
eMLPP Priority | eMLPP Priority | 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 | M | V | 1 |
SGSN number | SGSN number | C | TLV | 5-11 |
VLR number | VLR number | 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 | M | V | 1 |
SGSN number | SGSN number | C | TLV | 5-11 |
VLR number | VLR number | 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 | M | V | 1 |
IMSI | IMSI | M | TLV | 6-10 |
Cell global identity | Cell global identity | 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.