Routing

Routing

Routing Information Exchange Protocols TCP / IP

All routing information exchange protocols TCP / IP stack belong to a class of adaptive protocols, which in turn are divided into two groups, each associated with one of the following algorithms:

•Distance-vector algorithm (Distance Vector Algorithms, DVA),

•Link state algorithm (Link State Algorithms, LSA).

In distance-vector algorithms, such as every router periodically broadcast and distribute over the network from a vector of distances to all known networks. The distance is usually understood as the number of intermediate routers through which the packet must pass before you get into the proper network. It can be used and another metric that takes into account not only the number of transfer points, but the time of the packets on the connection between adjacent routers. Having obtained the vector from a neighboring router, each router appends information known to him the other networks, which he learned directly (if they are connected to its ports) or similar declarations of other routers, and then sends the new value of the vector through the network. In the end, each router learns about available networks in the internetwork and the distance to them by neighboring routers (Hartpence, 2011).

Algorithms for the state of each router relations provide information sufficient to construct an accurate graph of network connections. All routers operate on the basis of the same graph, which makes routing more resilient to changes in the configuration. Broadcast is used here only for changes in state bonds, which occurs in reliable networks are not so often.

In order to understand the condition of the communication line connected to its ports, the router periodically exchanging short packets with its immediate neighbors. This traffic is also broadcast, but it circulates only between neighbors, and so not clogs the network.

Most routing protocols used in today's packet-switched networks, are derived ...