Routing Management Policy - 3Com 7700 Configuration Manual

Routing Management
Policy
The priority added to the IP routing table for a route — Indicates the type of
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route that is selected. There may be multiple routes with different next hops to
the same destination. These routes can be discovered by different routing
protocols, or they can be the static routes that are configured manually. The
route with the highest priority (the smallest numerical value) is selected as the
current optimal route.
Types of routes are divided into the following subnet routes, where the destination
is a subnet, or host routes, where the destination is a host.
In addition, depending on whether the network of the destination host is directly
connected to the router, there are the following types of routes:
Direct route: The router is directly connected to the network where the
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destination is located.
Indirect route: The router is not directly connected to the network where the
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destination is located.
To limit the size of the routing table, an option is available to set a default route.
All the packets that fail to find a suitable table entry are forwarded through this
default route.
In a complicated Internet as shown in the following figure, the number in each
network is the network address. The router R8 is connected to three networks, so
it has three IP addresses and three physical ports, and its routing table is shown in
Figure 2.
Figure 2 The Routing Table
16.0.0.3
16.0.0.2
16.0.0.0
15.0.0.2
R6
16.0.0.2
15.0.0.0
13.0.0.2
15.0.0.1
13.0.0.0
R2
14.0.0.2
13.0.0.1
14.0.0.0
12.0.0.2
R1
14.0.0.1
12.0.0.0
12.0.0.3
The Switch 7700 supports the configuration of a series of dynamic routing
protocols such as RIP, OSPF, as well as the static routes. The static routes
configured by the user are managed together with the dynamic routes as detected
by the routing protocol. The static routes and the routes learned or configured by
routing protocols can also be shared with each other.
16.0.0.3
10.0.0.2
R7
R5
10.0.0.0
13.0.0.3
10.0.0.1
R8
11.0.0.1
13.0.0.4
11.0.0.0
R3
11.0.0.2
R4
12.0.0.1
IP Routing Protocol Overview
Destination
Forwarding Port
host
router passed
location
Directly
10.0.0
11.0.0 Directly
12.0.0 11.0.0.2
Directly
13.0.0
13.0.0.2
14.0.0
15.0.0 10.0.0.2
10.0.0.2
16.0.0
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2
1
1
3
3
2
2