Performance Evaluation of Video Streaming in an Infrastructure Mesh Based Vehicle Network

Most next-generation wireless networks are expected to support video stream- ing which constitutes the bulk of traffic on the Internet. This thesis evaluates the performance of video streaming in a vehicle network with an infrastructure wireless mesh network (WMN) backhaul. Several studies have investigated video quality per- formance primarily in single hop wireless networks and static WMNs. This thesis is based on those studies and conducts the study in relation to a network where the multi-hop features of the mesh network and mobility of the streaming clients may have substantial impact on the perceived video quality in the network. The study assumes a previously proposed vehicle network architecture con- sisting of an infrastructure WMN that serves as the mesh backhaul [2, 3]. A number of mesh routers (MRs) form the mesh backhaul using one of their two IEEE 802.11g radios whereas the other radio is used to communicate with the fast moving mesh clients (MCs). Selective MRs called mesh gateways (MGs) are connected to a wired network (e.g., the Internet, hereafter referred to as the core network) via a point-to- point link and provide gateway connectivity to the rest of the network. A server on the core network acts as a video server and streams individual video streams to the fast moving MCs. Upon deployment, network discovery occurs and segregates the network into a number of separate routing zones with each routing zone consisting of a single MG and all the MRs that use the MG as their gateway. A minimum-hop based routing protocol is used to enable seamless handover of MCs from one MR to another within a single zone. Simulation studies in this thesis inspects the network and video streaming performance within a single routing zone, assuming the handoff and inter-zone routing being taken care of by the routing protocol and only focus on the intra-zone packet forwarding and scheduling impacts. Hence, this study does not address cases where MCs move from one routing zone to another routing zone in the mobile network. In the first part of the study, we evaluate the performance of video streaming in the described network by studying performance metrics across different layers of the protocol stack. The number of video flows that can be supported by the network is experimentally determined for each scenario. In the second part, the thesis studies controllable network and protocol parameters\u27 ability to improve the network and video quality performance. Simulations are run in an integrated framework that includes network-simulator ns-2, NS-MIRACLE, and Evalvid