32.0053G call and event data for the Circuit Switched (CS) domain3GPPCharging managementRelease 1999Telecommunications managementTS
Figure B.2 illustrates a simple incoming call from a fixed network subscriber "A" to a PLMN subscriber "B".
The incoming call is first routed to a GMSC (1). The GMSC shall create an incoming gateway record for fixed network accounting purposes to record the point at which the call entered the network together with the time stamps required to calculate the holding time of the incoming trunk and the conversation duration. This gateway record shall contain the IMSI of the called subscriber.
The GMSC interrogates the HLR of the called subscriber in order to determine his current location (2). The HLR shall create an HLR interrogation event record.
The GMSC routes the call to the MSC at which the subscriber is currently registered (3). This terminating MSC (MSC-B) shall create an MTC record for subscriber "B".
For the avoidance of doubt, even if the MSC and GMSC are co-located both the MTC and gateway records shall be produced.
The records generated are subsequently transferred to the OS either on release of the connection or when collected by the OS (A).
Figure B.2: Land to mobile (incoming) call