"call-level" and "burst-level" priorities for an effective management of multimedia services in UMTS

It is not an easy task in the UMTS environment to effectively design the transport and the management of traffic belonging to multimedia teleservices, due to the difficult communication requirements of such applications. It is proposed to contemporary use at the "transport" layer of the system several bearers, one for each traffic component of the multimedia service. Furthermore, a two-level (static and dynamic) priority mechanism is to be adopted by the higher protocol levels of the UMTS for the adaptation of call set-up, channel access, and admission control procedures to the nature of the multimedia services and to optimise the sharing of radio channel resources and the management of the reservation buffer. The results achieved demonstrate that the proposed mechanism shows a good performance especially during periods in which the system traffic load is high and reacts well to the worsening of the multimedia service quality, both in terms of information loss and synchronisation of its traffic components.