End-to-end quality-of-service coordination for mobile multimedia applications

Transmitting real-time multimedia streams over heterogeneous mobile networks is a challenging task. Variation in network and system conditions can dramatically affect application performance. When providing end-to-end quality-of-service (QoS) multiple system facets should be coordinated: orchestration of local and peer resources, reservation of network resources, adaptation of multimedia streams, etc. This paper presents an end-to-end negotiation protocol (E2ENP) for negotiating and coordinating QoS on an end-to-end basis both at application and network layer. Based on a flexible extensible markup language (XML) model and extending SDPng concepts, the protocol enables the negotiation of system capabilities and allows provider-services to effectively influence the negotiation process. The aim of the E2ENP design is to optimize the efficiency of multimedia call setup and reduce the time for QoS renegotiations, whenever vertical handovers or spontaneous network reconfigurations occur. The basic protocol is presented, together with implementation and measurement results, stemming from several studies on current and future third-generation/fourth-generation scenarios.