Implementing a Protocol for Maintenance and Construction of Network Topologies in TOWN

The goal of the TOWN project is to lay the technical foundations for ASCOM to build routers with multiple IEEE 802.16-2004 interfaces that can form wireless multi-hop networks for disaster recovery in a self-organized way. The main scope of this report is the design of a protocol that im- plements a previously proposed topology construction and channel al- location algorithm in a TOWN network. The protocol is inspired by OSPF. Each router tracks the state of all links in the network with its own copy of a network database. Additionally, each routers tracks scan results of all potential links in the network. Changes in link states and new scan results are opportunistically flooded through the network. A conflict resolution protocol resolves possible inequalities between neighboring routers. A modified Dijkstra algorithm running locally ensures that router joins lead to network topologies that are op- timized for capacity and load balancing. This algorithm also includes a greedy channel allocation to minimize interference of wireless routers in range. For a proof of concept, we head towards implementing the protocol in a test environment which we call demonstrator. The demonstrator is a well equipped PC which hosts up to three dozens of virtual routers running the protocol. We review issues concerning the implementation of this demonstrator such as how to drive this emulation and how to emulate the wireless network. Finally, we conclude with a summary, time and implementation plan.