Message Type

By

Description

Identification Request/Re- sponse

GTP-C

Sent by the new SGSN to the old SGSN to request the IMSI for a MS when a GPRS Attach is done with a P-TMSI and the MS has changed SGSNs since the GPRS Detach was done.

SGSN context Request/ Response/ Acknowledge

GTP-C

Sent by the new SGSN to the old SGSN to request the MM and

PDP Contexts for the MS.

Forward Relocation Request/ Response/ Complete/ Com- plete Acknowledge

GTP-C

Indicates mobile activation/deactivation within a Routing Area. This prevents paging of a mobile that is not active (visited VLR rejects calls from the HLR or applies Call Forwarding). Note that the mobile station does not maintain an attach/detach state.

SRNS contexts contain for each concerned RAB the sequence numbers of the GTP-PDUs next to be transmitted in uplink and downlink directions.

Relocation Cancel Request/ Response

GTP-C

Send to cancel the relocation of a connection.

Forward SRNS Context/ Con- text Acknowledge

GTP-C

This procedure may be used to trigger the transfer of SRNS con- texts from RNC to CN (PS domain) in case of inter system for- ward handover.

Forward the Routing Area Network (RAN) information.

RAN Information Relay

GTP-C

A Routing Area (RA) is a subset of a GSM Location Area (LA). A RA is served by only one SGSN. Ensures that regular radio con- tact is maintained by the mobile

MBMS messages

Message Type

By

Description

MBMS Notification Request/ Response/ Reject Request/ Reject Response

GTP-C

Notification of the radio access devices.

Create MBMS Context

Request/ Response

GTP-C

Request to create an active MBMS context. The context will be pending until the response is received.

Once active, the MBMS context allows the MS to receive data from a specific MBMS source