scope:

This Technical Specification (TS) contains the stage 2 service description for a High Speed Circuit Switched Data (HSCSD) on GSM.

In analogy with CCITT Recommendations I.130 [6] (refer to annex A) and with reference of CCITT Recommendations VI.1 Q.65 [7] (Stage 2 of the method for characterization of services supported by an ISDN), the second stage of the HSCSD is defined as follows.

Stage 2 identifies the functional capabilities and information flows needed to support the service as described in High Speed Circuit Switched Data (HSCSD) - Stage 1, GSM 02.34 [9]. Furthermore, it identifies various possible physical locations for the functional capabilities. The output of Stage 2, which is signalling system independent, is used as an input to Stage 3, the design of signalling system and switching Recommendations.