This TS provides the description of the Subnetwork Dependent Convergence Protocol (SNDCP) for the General Packet Radio Service (GPRS).
The user of the services provided by SNDCP is a packet data protocol (PDP) at the mobile Station (MS) or the Relay at the Serving GPRS Support Node (SGSN). Additionally, a control entity, e.g., AT command interpreter, may be an SNDCP user. SNDCP uses the services provided by the Logical Link Control (LLC) layer and the Session Management (SM) sub-layer.
The main functions of SNDCP are:
Multiplexing of several PDPs.
Compression / decompression of user data.
Compression / decompression of protocol control information.
Segmentation of a network protocol data unit (N PDU) into Logical Link Control Protocol Data Units (LL PDUs) and re-assembly of LL PDUs into an N PDU.
This TS is applicable to GPRS MS and SGSN.