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Abstract-In order to solve the problem of routing protocols using the Distributed Bellman-Ford (DBF) algorithm converge very slowly to the correct routes when link costs increase, and in the case when a set of link failures results in a network unavailable. We propose a new fast converge distance vector routing paradigm FC-DVRP where the goal is to reduce times of routes triggered convergence, in the meantime insure network availability. To this end, we present a suppression-failure strategy and multiple feasible backups per destination for every node. The analysis result show that FC-DVRP provide better network stability and availability, and the simulation experiments show that FC-DVRP can improve survivability of the network effectively.
Index Terms-distance vector routing; fast convergence; backup node; triggered convergence; network survivability
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I. INTRODUCTION
Routing protocols construct tables at each node that specify for each destination the next-hop to use for data packet forwarding. It is required that the routing tables computed by them be free of loops when the network is stable. In dynamic environments, a more stringent requirement is that the routing tables be loop-free not only when network is stable but at every instant because, loops even if temporary can rapidly degrade performance. In order to solve this problem traditional distributed routing have to globally propagate messages triggered by certain events such as link failures in ensuring forwarding continuity. Convergence period depends on the network size and speed of processing. In the largescale network (thousands of nodes), these protocols take seconds to resume forwarding. Reducing convergence period is crucial in the design of routing protocols. The attempts to solve this problem in the literature can be roughly classified into two categories: (a) reducing the convergence period of protocols, and (b) suppurating or eliminating the advertisement of failure and locally rerouting packets during the suppression period.
The first category of proposals involves link-state protocols can through reducing convergence period by tweaking protocol parameters (such an LSA propagation timers and periodicity of HELLO messages) [1]. BGP [2] speeds up convergence through reducing the duration of propagating notifications, such as MRAI [3] can speed up the convergence of the network. Although these solutions can improve the convergence time of routing protocols, they also run the risk of...