It also receives a similar list from each neighbor. Once every T msec, each router sends to each neighbor a list of its estimated delays to each destination. If the metric is propagation delay, the router can measure it directly with special ECHO packets that the receiver just timestamps and sends back as fast as it can.Īs an example, assume that delay is used as a metric and that the router knows the delay to each of its neighbors. If the metric is hops, the distance is just one hop. The router is assumed to know the ‘‘distance’’ to each of its neighbors. The distance might be measured as the number of hops or using another metric. This entry has two parts: the preferred outgoing line to use for that destination and an estimate of the distance to that destination. In distance vector routing, each router maintains a routing table indexed by, and containing one entry for each router in the network.

The distance vector routing algorithm is sometimes commonly known as distributed Bellman-Ford routing algorithm. Eventually, every router knows the best link to reach each destination. These tables are updated by exchanging information with the neighbors. A distance vector routing algorithm operates by having each router maintain a table (i.e., a vector) giving the best known distance to each destination and which link to use to get there. Two dynamic algorithms in particular, distance vector routing and link state routing, are the most popular. The best path is the one that gives minimum end-to-end delay and with the greatest available bandwidth.Ĭomputer networks generally use dynamic routing algorithms that are more complex than flooding, but more efficient because they find shortest paths for the current topology. Routing is a major component of the network layer and is concerned with the problem of determining feasible paths (or routes) for packets to follow from each source to each destination. It is done by a network layer protocol called IP (Internetworking Protocol). Packetizing: The network layer encapsulates the packets received from upper layer protocol and makes new packets. This is called as routing and it depends on various criterions. The network layer decides the root to be taken. Routing: In a network, there are multiple roots available from a source to a destination and one of them is to be chosen. The address used in the network layer should uniquely and universally define the connection of a computer. It provides the logical connection between different types of networks.Īddressing: Addressing is necessary to identify each device on the internet uniquely. Internetworking: This is the main duty of network layer.

Distance vector routing protocol list