Countering Count-To-Infinity in High Speed Networks

Routing tables of all the routers needs frequent updates due topology changes resulting because of link failures or link metric modifications. Each of those updates may cause transient routing loops. These loops pose significant stability problems in Wireless Networks. Distributed routing algorithms capable of avoiding such transient loops in network path are deemed efficient. Some earlier approaches like Shortest path routing (Dijkstra) etc. have problems maintaining the balance between node delays and link delays. Besides an earlier algorithm, Distributed Path Computation with Intermediate Variables (DIV) guarantees steady-state, with no transient loops. It’s ability to operate with existing distributed routing algorithms to guarantee that the directed graph induced by the routing decisions stays acyclic by implementing an update mechanism using simple message exchanges between neighboring nodes that guarantees loop freedom at all times. It outperforms existing loop prevention algorithms in several key metrics such as frequency of synchronous updates and the ability to maintain paths during transitions. But still frequency of updates is still an open issue and we address that problem specifically by implementing and using proactive source routing (PSR) protocol. Compared to existing routing protocols,It requires no timestamp for routing updates. In PSR the update messages are easily integrated into the tree structure, so that the computation overhead can be significantly reduced.