Link State Routing Protocol Operation

Link state routing protocols use Dijkstra’s algorithm, commonly known as Shortest Path First (SPF) algorithm. SPF accumulates each path’s cost along the way form source to destination. Each router chooses the best route that has the least metric. Upon receiving link state information from other routers, each router builds its own tree topology of the entire network.   1-     Routers identify themselves and gather information about other directly connected routers; this is done by exchanging Hello packets from which they can build the Neighbour Table.2-    ...

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Link State Routing Protocol

In contrast to Distance Vector protocols which use only distance and metric to determine the best path, Link state protocols do not distribute any routes, instead, they exchange the network topology information that describe the network....

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Advantages and Disadvantages of Distance Vector Routing Protocol

Distance Vector is a relatively simple approach and easy to use, implement and maintain and does not require High-level knowledge to deploy. Moreover, it does not demand high bandwidth level to send their periodic updates as the size of the packets are relatively small. Furthermore, distance vector protocols do not require a large amount of CPU resources or memory to store the routing data. The main drawbacks of Distance Vector are limited scalability due to slow convergence time, bandwidth consumption and routing loops.“Convergence time is the time needed for all routers within a single routing domain to receive, process and build their routing table” (Osterloh, 2002). Because RIP routers must fully process the updates they receive and then wait for 30-second interval before sending...

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Distance Vector Routing Protocols Operation

Routers that use distance vector periodically broadcast their entire routing table to its neighbours even if the network topology has not changed. These periodic updates are sent at regular intervals (normally 30 seconds for RIP and 90 seconds for IGRP). This is achieved by means of local timer maintained in each router in the network, when the timer expires; a routing information update is sent (Graziani & Johnson, 2009).    Distance Vector Periodic Updates Distance Vector protocol is mathematically based on Bellman-Ford algorithm. Because of the algorithm simplicity,...

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Distance Vector Dynamic Protocols

Distance Vector is one way to classify a routing protocol based on the algorithm type used to build and sustain their routing tables (Graziani & Johnson, 2009). Largely, Distance Vector routing protocols have been used for many years by network administrators to overcome the problems that arose when using static routing configuration. It selects the best path based on how far the destination is, regardless of link load, reliability or delay. Normally, Distance is calculated by the number of hops or by a combination of parameters that represent distance. Distance Vector routing protocol include Routing Information protocol (RIP), Interior...

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Introduction to Dynamic Routing Protocols

In large-scale networks, routing protocols play a vital role to keep the network up and running. Routers use dynamic protocols to first learn about the directly connected routers, then learn about routes that have been advertised from other routers and finally build its own list (Routing Table) to be able to determine the best path to destination networks. A Routing Protocol is a set of procedures based on algorithm that the router uses to exchange routing information with other routers. It provides dynamic reaction mechanism for network topology changes as well as notifying other routers of a change. In addition, dynamic routing protocols will find an alternate path around topology changes to keep the network in operation. The most common classes of dynamic routing protocols are Distance...

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