Answer to Question #164488 in Computer Networks for Eeshal

Question

Scenario:

AETMAD Bank is a modern and well reputed bank having 200 branches in various cities of a country. The branches are connected with each other through a grand computer network comprising of more than 1000 computers, 200 routers and a number of other related nodes such as switches, printers and scanners etc. The employees of the bank are often rotated among different branches causing change in the number of nodes per branch. In case of employee rotation, some hosts may be added in a branch and some may be removed resulting in change in the overall network topology. The bank is progressing day by day and having goal to expand its services by opening further branches in different cities of the country. The network executive of the bank has been asked to implement most suitable type of routing which would be easy to handle for the well trained networking staff to deal with scalability, any possible complexity and to maintain the overall efficacy of the network.

Question:

After carefully analyzing the above mentioned scenario and requirements of the bank, suggest the most suitable type of routing from the following with two proper reasons:

1. Distance Vector
2. Link State

Answer 1

Link state - are routing protocols that share information with other routers in order to determine the path to be used. For AETMAD Bank, I would choose these protocols because;

i) Link-state protocols use LSA (Link State Advertisement) floods and triggered updates to immediately report changes in the network topology to all routers in the network with little overhead. Because AETMAD is a big organization, its computer network is very big, therefore, needs immediate changes to be reported, like the rotation of employees. This might cause changes in the IP network such as changes in the size of Virtual LANs (VLANS) in the department.

ii)     Link state use cost metrics to determine the path through the network. This is important to AETMAD bank because the most efficient path should be used so as to reach its destination as soon as possible because a lot of packets need to be transmitted. This is better compared to distance vector protocols which use next-hop as the cost metric. A path might have more hops but have more bandwidth and less congestion.