Mobile service-oriented content delivery in wireless mesh networks

Abstract

Wireless mesh networks (WMN) is poised to be a cost-effective platform for many municipal applications in public safety, business and entertainment. In this paper we present WMN-based platform for content delivery within Intelligent Transportation Systems (ITS) applications. An example ITS application would be to deliver content used for vehicle route guidance in emergency evacuation situations. The characteristics of ITS applications of higher vehicle speeds and of the limited coverage of WMN (wi-fi) mesh router causes more frequent handoffs which complicates content delivery over wireless mesh networks. Frequent handoffs mandate smaller handoff delay. Using standard IEEE handoffs may cause unacceptable interruption in content delivery. We propose a service-oriented mobility management protocol (SMMP) for ITS content delivery. Within the protocol, content is considered as services described by XML metadata files. The protocol takes advantage of a hierarchical organization of WMN routers to reduce the handoff delay. The quasi-stationary nature of WMN mesh routers enables the detection of the sequence of routers that a vehicle will be in connection with. SMMP provides to the traveling vehicles cached MAC addresses of WMN mesh routers to communicate with. We evaluate the benefits of the proposed protocol and compared it to the traditional solutions using OMNET++ simulator. Our results show that using SMMP reduces handoff latencies and improves the overall network throughput at lower and higher vehicle speeds.