Section: 4.1.1.1 Types of MM and GMM procedures
Content: Depending on how they can be initiated, three types of MM procedures can be distinguished: 1) MM common procedures: A MM common procedure can always be initiated whilst a RR connection exists. The procedures belonging to this type are: Initiated by the network: - TMSI reallocation procedure; - authentication procedure; - identification procedure; - MM information procedure; - abort procedure. However, abort procedure is used only if an MM connection is being established or has already been established i.e. not during MM specific procedures or during IMSI detach procedure, see subclause 4.3.5. Initiated by the mobile station: - IMSI detach procedure (with the exceptions specified in subclause 4.3.4). 2) MM specific procedures: A MM specific procedure can only be initiated if no other MM specific procedure is running or no MM connection exists. The procedures belonging to this type are: - normal location updating procedure; - periodic updating procedure; - IMSI attach procedure; and - eCall inactivity procedure. 3) MM connection management procedures: These procedures are used to establish, maintain and release a MM connection between the mobile station and the network, over which an entity of the upper CM layer can exchange information with its peer. A MM connection establishment can only be performed if no MM specific procedure is running. More than one MM connection may be active at the same time. Depending on how they can be initiated, three types of GMM procedures can be distinguished: 1) GMM common procedures: In Iu mode, a GMM common procedure can always be initiated whilst a PS signalling connection exists. The procedures belonging to this type are: Initiated by the network when a GMM context has been established: - P-TMSI (re-) allocation; - GPRS authentication and ciphering; - GPRS identification; - GPRS information. 2) GMM specific procedures: Initiated by the network and used to detach the IMSI in the network for GPRS services and/or non-GPRS services and to release a GMM context: - GPRS detach. Initiated by the MS and used to attach or detach the IMSI in the network for GPRS services and/or non-GPRS services and to establish or release a GMM context: - GPRS attach and combined GPRS attach; - GPRS detach and combined GPRS detach; - eCall inactivity procedure. Initiated by the MS when a GMM context has been established: - normal routing area updating and combined routing area updating; - periodic routing area updating. 3) GMM connection management procedures (Iu mode only): Initiated by the MS and used to establish a secure connection to the network and/or to request the resource reservation for sending data: Service Request. The Service Request procedure can only be initiated if no MS initiated GMM specific procedure is ongoing.