Tree-based link-state routing in the presence of routing information corruption

Traditionally, link-state routing (LSR) uses two costly techniques to achieve its robustness and responsiveness: message forwarding on every communication link in the broadcast of network status updates, and the periodic broadcast of local status by every router. In this paper, we present a novel LSR protocol, called tree-based LSR (T-LSR), which reduces the operational overhead of LSR as follows. A leader router is elected to periodically broadcast network status on behalf of all the other routers in the network, and a spanning tree is constructed to support these broadcasts. The T-LSR protocol distinguishes itself from previous tree-based, lightweight LSR methods by its fault-tolerance features: the T-LSR protocol is shown to maintain consistent routing information and leader preferences throughout the network in the presence of undetected transmission/information corruption problems. The results of a simulation study demonstrate that the T-LSR protocol imposes a small fraction of the overhead of conventional LSR.