H3C Technologies H3C WX3000E Series Wireless Switches - Manual (Page 142)

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Table 10 Dynamic routing protocols
Criterion Categories
Optional scope
• Interior gateway protocols (IGPs)—Work within an autonomous system (AS). Examples
include RIP, OSPF, and IS-IS.
• Exterior gateway protocols (EGPs)—Work between ASs. The most popular one is BGP.
Routing
algorithm
• Distance-vector protocols—RIP and BGP. BGP is also considered a path-vector protocol.
• Link-state protocols—OSPF and IS-IS
Destination
address type
• Unicast routing protocols—RIP, OSPF, BGP, and IS-IS
• Multicast routing protocols—PIM-SM and PIM-DM
IP version
• IPv4 routing protocols—RIP, OSPF, BGP, and IS-IS
• IPv6 routing protocols—RIPng, OSPFv3, IPv6 BGP, and IPv6 IS-IS
NOTE:
The WX3000E Series Wireless Switches support only RIP.
Routing preference
Different routing protocols may find different routes to the same destination. However, not all of those
routes are optimal. For route selection, routing protocols, direct routes, and static routes are assigned
different preferences. The route with the highest preference is preferred.
The preference of a direct route is always 0 and cannot be changed. All other types of routes can have
their preferences manually configured. Each static route can be configured with a different preference.
The following table lists the types of routes and the default preferences. The smaller the preference value,
the higher the preference.
Routing approach Preference
Direct route 0
Static route 60
RIP 100
Load sharing
A routing protocol can be configured with multiple equal-cost routes to the same destination. These routes
have the same preference and will all be used to accomplish load sharing if there is no route with a
higher preference available.
Route backup
Route backup can help improve network reliability. With route backup, you can configure multiple routes
to the same destination, expecting the one with the highest preference to be the main route and all the
rest backup routes.
Under normal circumstances, packets are forwarded through the main route. When the link fails, the
route with the highest preference among the backup routes is selected to forward packets. When the link