Caching and scheduling mechanisms for H.264 video flow delivery over discontinuous coverage wireless networks

摘要

The past few years have witnessed the deployment of a wide variety of multimedia applications over wireless networks. As a consequence, mobile users are demanding fast and efficient connectivity, especially concerning start-up delays and flow quality. Wireless networks aim at providing an everywhere coverage without spending prohibitive deployment costs. Thus, the coverage of each access point is extended with detriment to the mean throughput of the radio cell. The coverage is continuous, but radio conditions met by users are not homogeneous. Actually, data rate is varying according to user mobility. In the context of streaming applications, intermittent high rate availability may lead to service disruption, especially when user's number increases. Thus, it is essential to design a network architecture able to efficiently deliver video flows to mobile users. In our works, a new equipment, called network cache, is introduced. The latter performs efficient flow caching and scheduling, in order to guarantee service continuity. The simulation shows that the proposed architecture gives satisfying service start-up delays and improves system scalability.