Terrestrial Trunked Radio (TETRA); Voice plus Data (V+D); Part 3: Interworking at the Inter-System Interface (ISI); Sub-part 4: Additional Network Feature Short Data Service (ANF-ISISDS)
The present document defines the Terrestrial Trunked Radio system (TETRA) supporting Voice plus Data (V+D). It specifies: - general design aspects (e.g. reference points, numbering and addressing, or protocol architecture); - the system bearer and mobility management services, and the corresponding air interface protocols; - the interworking between TETRA networks; - the interworking of TETRA networks with other networks, via gateways; - the peripheral equipment interface on the mobile station; - the Line Station (LS) interface with TETRA networks; - the security protocols and mechanisms applicable to TETRA networks and to TETRA terminal equipment;