Routing Algorithm:- The Algorithm that manages the Routing Tables and makes the Routing Decisions is called Routing Algorithm.
Implementation of Connection – Oriented Network layer Service:-
- In this service the sub net is called Virtual Circuit Sub net.
- A path from Source Router to Destination Router is established before sending any packets. That Router is used for all traffic flowing over that connection.
Ex:- A Telephone System.
- When connection is released, the virtual circuit is also terminated.
Let us see an example, The figure shows the routing using Virtual Circuit sub net, In this Host H1 wants to send packets to H2
Now H1 will establishes a connection 1 with Host H2 whenever packet comes from host H1 , we use connection 1 with identifier as 1. i.e, from routing table of A , a packet is coming from H1 , identifier is 1 then use the outgoing router C with identifier 1 .
Similarly for H3 use identifier as 2. This is called as label Switching .
The comparison between these connection oriented and connection less services or Virtual circuit or data gram sub nets is given in the table.