Dynamic routing protocols can be classified based on the following criteria.
Based on the application scope, routing protocol types can be defined as follows:
Interior Gateway Protocol (IGP): runs within an Autonomous System (AS), such as RIP, OSPF, and IS-IS.
Exterior Gateway Protocol (EGP): runs between ASs. At present, BGP is the most widely used EGP.
Based on the routing algorithm, routing protocol types can be defined as follows:
Distance-vector routing protocol: includes RIP and BGP. BGP is also called a path-vector protocol.
Link-state routing protocol: includes OSPF and IS-IS.
These routing algorithms differ in their methods of discovering and calculating routes.
Based on the destination address type, routing protocol types can be defined as follows:
Unicast routing protocol: includes RIP, OSPF, BGP, and IS-IS.
Multicast routing protocol: includes Protocol Independent Multicast-Sparse Mode (PIM-SM).
This chapter describes unicast routing protocols only. For details on multicast routing protocols, see the HUAWEI NetEngine 8000 F Series Router Feature Description - IP Multicast.
Routers manage both static and dynamic routes. These routes can be exchanged between different routing protocols to implement readvertisement of routing information.