H3C Technologies H3C WX6000 Series Access Controllers - Manual (Page 205)

21-3
Routing Protocol Overview
Static Routing and Dynamic Routing
Static routing is easy to configure and requires less system resources. It works well in small, stable
networks with simple topologies. Its major drawback is that you must perform routing configuration
again whenever the network topology changes; it cannot adjust to network changes by itself.
Dynamic routing is based on dynamic routing protocols, which can detect network topology changes
and recalculate the routes accordingly. Therefore, dynamic routing is suitable for large networks. Its
disadvantages are that it is complicated to configure, and that it not only imposes higher requirements
on the system, but also eats away a certain amount of network resources.
Classification of Dynamic Routing Protocols
Dynamic routing protocols can be classified based on the following standards:
Operational scope
z
Interior gateway protocols (IGPs): Work within an autonomous system, including RIP, OSPF, and
IS-IS.
z
Exterior gateway protocols (EGPs): Work between autonomous systems. The most popular one is
BGP.
An autonomous system refers to a group of routers that share the same routing policy and work under
the same administration.
Routing algorithm
z
Distance-vector protocols: RIP and BGP. BGP is also considered a path-vector protocol.
z
Link-state protocols: OSPF and IS-IS.
The main differences between the above two types of routing algorithms lie in the way routes are
discovered and calculated.
Type of the destination address
z
Unicast routing protocols: RIP, OSPF, BGP, and IS-IS.
z
Multicast routing protocols: PIM-SM and PIM-DM.
This chapter focuses on unicast routing protocols. For information on multicast routing protocols, refer
to the Multicast Protocol in H3C WX6103 Access Controller Switch Interface Board Configuration
Guide .
Version of IP protocol
IPv4 routing protocols: RIP, OSPFv2, BGP4 and IS-IS.
IPv6 routing protocols: RIPng, OSPFv3, IPv6 BGP, and IPv6 IS-IS.