3.5.a Describe packet types

3.5.a [ii] Route types [internal, external]

EIGRP has the concept of internal and external routes. Internal routes are ones that have been originated within an EIGRP autonomous system (AS). Therefore, a directly attached network that is configured to run EIGRP is considered an internal route and is propagated with this information throughout the EIGRP AS. External routes are ones that have been learned by another routing protocol or reside in the routing table as static routes. These routes are tagged individually with the identity of their origination.

External routes are tagged with the following information:

● The router ID of the EIGRP router that redistributed the route.

● The AS number where the destination resides.

● A configurable administrator tag.

● Protocol ID of the external protocol.

● The metric from the external protocol.

● Bit flags for default routing.

Adam, Paul (2014-07-12). All-in-One CCIE V5 Written Exam Guide (Kindle Locations 3049-3051).  . Kindle Edition.