Answer:
Comparison between centralized and decentralized routing algorithms:
The major similarity between both centralized and decentralized routing algorithms is that they are both communication serving systems. They both utilize node system(e.g, computer) and are both a communication liking system( e.g, Cable).
Contrasting between centralized and decentralized routing algorithms:
There are few differences between these two type of communication link or path way system but to name a couple of them,
For centralized, there is a single client server distribution node which simply means that one or more client server system are connected to a central processing server.
This also means that if the central processing server or pathway fails, it leads to the failure of the entire system. That is, there is no sending, responding or general processing of any form of requests. Example of a system that uses the centralized routing algorithm is the google search engine.
WHILE:
for the decentralized routing algorithms, there are multiple client server distribution pathway and each server makes its own decision. Here,there is no single entity that receives and responds to the request therefore,failure of any form of central path way processing node does not lead to the failure of the whole system unlike for the centralized system.
Advantages of centralized routing algorithm:
It can be easily protected or secured due to the nature of the system. If the central node is been secured, it generally translate to the different client node being secured.
It is easy to disconnect a connected client node from the central pathway node or central server as the case may be.
Disadvantages of centralized routing algorithm:
The client nodes are totally dependent on the central node or server so if there is a failure in the central server, the client node is then totally shut down.
Advantages of decentralized routing algorithm:
There is a random distribution of data on all the processing node or server which automatically creates a form of balance within the system. This leads to minimal or no down time processing client request.
Disadvantages of decentralized routing algorithm:
Due to the nature or fact that there are multiple processing system for different client node, it is difficult to detect which client node or request processing server is faulty. This can lead to delay in the fixing of fault in the system should it arise.
Why do we prefer a ""decentralized"" algorithm for routing messages through the internet?
The major reason why decentralized algorithm routing is preferred is because of the level of security attached to it. Each processing servers are secured independently and there is privilege of utilizing independent networking system.