Analyzing Routing in the Network's Access Layer

Access layer routers can normally be classified as stub or dual-homed. The sections that follow present each type along with alternative methods of supporting them.

Stub Sites

Stub sites are those that have only a single path into the rest of the network and typically have very few routes to advertise upstream. True stub sites do not have dial backup or any other way that they could gain an additional path into the distribution layer. As such, true stubs are fairly rare.

There are generally two (obvious) ways to handle stubs: running EIGRP out to them (allowing them to advertise their locally connected networks) or not running EIGRP out to them.

If EIGRP is running out to the stub site's remote ...

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