This Standard specifies the signalling protocol for the support of the Short Message Service (SMS) at the Q reference point between Private Integrated services Network eXchanges (PINXs) connected together within a Private Integrated Services Network (PISN).
This service is based on GSM 03.40. The Service Centre functionality described in this Standard is equal to the functionality of a Service Centre in GSM 03.40. Thus, for interoperability with a GSM network, it is only necessary to implement a QSIG interface.
NOTE 1 – The Short Message Service is a special type of basic service but is described in the present document as a supplementary service.
The Short Message Service is a service which permits a served user to send a message of limited size to another user in the same PISN or another network.
The Q reference point is defined in ECMA-133.
Service specifications are produced in three stages and according to the method specified in ETS 300 387. This Standard contains the stage 3 specification for the Q reference point and satisfies the requirements identified by the stage 1 and stage 2 specifications in ECMA-324.
The signalling protocol for SMS operates on top of the signalling protocol for the connection oriented call independent APDU transport mechanism and uses certain further aspects of the generic procedures for the control of supplementary services specified in ECMA-165.
This Standard also specifies additional signalling protocol requirements for the support of interactions at the Q reference point between SMS and supplementary services and ANFs.
This Standard is applicable to PINXs which can be interconnected to form a PISN.
The protocol defined in this Standard forms part of the PSS1 protocol (informally known as QSIG).