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An administrator also can statically assign these directions to the router.
6.5.2 Static Versus Dynamic Routes
Static route knowledge is administered manually by a network administrator who enters
it into a router’s configuration. The administrator must update this static route entry manually
whenever an internetwork topology change requires an update. Dynamic route knowledge
works differently. After a network administrator enters configuration commands to start
dynamic routing, the route knowledge automatically is updated by a routing process whenever
new information is received from the internetwork.
Changes in dynamic knowledge are exchanged between routers as part of the update
process.
6.5.3 The Purpose of a Static Route
Static routing has several useful applications. Dynamic routing tends to reveal
everything known about an internetwork; for security reasons, however, you might want to
hide parts of an internetwork. Static routing enables you to specify the information that you
want to reveal about restricted networks. When a network is accessible by only one path, a
static route to the network can be sufficient. This type of network is called a stub network.
A stub network is an OSPF area that carries a default route, intra-area routes, and
interarea routes, but that does not carry external routes. Configuring static routing to a stub
network avoids the overhead of dynamic routing, as shown in Figure 6-9 shown a Static Route
Operation.
Figure 6 - 9 shown a Static Route Operation
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