METHOD FOR ACHIEVING END-TO-END QUALITY OF SERVICE NEGOTIATIONS FOR DISTRIBUTED MULTI-MEDIA APPLICATIONS

This invention presents a framework for achieving dynamic End-to End QoS negotiation and control coordination, with distributed multimedia applications. The framework builds upon dynamic capability negotiations and specification of Adaptation Paths and (alternative) QoS Contracts, based on user preferences. In particular we present a protocol providing End-to-End negotiation of alternative QoS, capabilities, and preferences/configurations, based on extensions of IP-based protocols like SIP/RTSP/SDP, in coordination with mechanisms for network resource reservation (e.g. RSVP), local terminal resource (e.g. CPU, memory, power, auxiliary devices) reservation, and adaptation mechanisms. To this extent, and with respect to two or more peers (101, 103) this invention identifies six phases, through which said peers can establish multiparty, multi-stream, multimedia communications. In detail, the phases are: Protocol Discovery (104), Pre-Negotiation (106), Multi-Stream QoS Synchronization and QoS Correlation (107), Fast-Negotiation (obeying the Economy Principle) (108), Re-Negotiation (obeying the Economy Principle) (109), Resource Reservation Release (110). All the six phases can be concatenated, or be executed at different times. This invention also presents the concept of the E2ENP Broker (105), an optional third-party entity, which can be used for relieving peers (101, 103) from performing the time- and resource-consuming Pre-Negotiation phase (106) (and eventually also the Multi-Stream QoS Synchronization and QoS Correlation (107). This entity may coincide with e.g. audio-/videoconference bridges.