scope:

This technical specification specifies the procedures used at the radio interface (Reference point Um as defined in technical specification GSM 04.02) for normal operation and invocation of multi party supplementary services.

In technical specification GSM 04.10 the general aspects of the specification of supplementary services at the layer 3 radio interface are given.

Technical specification GSM 04.80 specifies the formats and coding for the supplementary services.

Definitions and descriptions of supplementary services are given in technical specification GSM 02.04 and the GSM 02.8x and 02.9x-series. Technical specification GSM 02.84 is related specially to multi party supplementary services. Technical realization of supplementary services is described in technical specification GSM 03.11 and the GSM 03.8x and 03.9x-series. Technical specification GSM 03.84 is related specially to multi party supplementary services. The procedures for Call Control, Mobility Management and Radio Resource management at the layer 3 radio interface are defined in technical specifications GSM 04.07 and GSM 04.08. The following supplementary service belongs to the multi party supplementary services and is described in this technical specification: - Multi party service (MPTY) (section 1).