03-04-2010, 10:47 AM
ABSTRACT
The complete network of large number of interconnected autonomous system, each of which consists of a distinct domain, needs to communicate to different nodes to forward the information. There are various means of communications between these systems. Routing is one of them. Routing refers to the overall network wide process that determines end to end paths that datagram will take from source to destinations. There are different routing algorithms available such as BELLMAN FORD ALGORITHM which is decentralized routing algorithm and DIJKSTRA ALGORITHM which is a global routing algorithm. In global routing algorithm, each router has a complete view of the network, whereas in a decentralized routing algorithm each router has a local view consisting of its directly attached neighbours. Out of this Dijkstra Algorithm is mostly preferred as it is faster as compared to any other algorithm and its implementation is easier. In this algorithm, router based information that has been collected from other routers, builds a graph of the network which shows the locations & links of routers within themselves & in the network. These links are labeled with a number called weight or cost. If there are two links between a node and destination, the router chooses the page link with the lowest weight.
One of the chief advantages of Dijkstra Algorithm is that router computes routes independently using the same original status data; they do not depend on the computation of intermediate machines. Because page link status messages propagate unchanged, it is easy to debug problems. Because routers perform the route computation locally, it is guaranteed to converge. Finally, because page link status messages only carry information about the direct connections from a single router, the size does not depend on the number of networks in the networks in the internet. Thus, Dijkstra Algorithms scale better than distance vector algorithms. We have implemented Dijkstra Algorithm for routing purpose.
Presented By:
Sriram Narayanan
BE- Electronics
NJIT
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http://web.njit.edu/~sn3/Project_College.pdf