EIGRP Summary

   EIGRP Summary

The characteristics of EIGRP follow:

-         Hybrid routing protocol (distance vector that has link-state protocol characteristics).

-         Use DUAL, first proposed by E. W. Dijkstra and C. S. Scholten, to perform distributed shortest-path routing while maintaining freedom from loops at every instant. Although many researchers have contributed to the development of DUAL, the most prominent work is that of J. J. Garcia-Luna-Aceves.

-         Cisco Proprietary created in 1994.

-         First released in IOS 9.21

-         Uses IP protocol 88.

-         Makes Automatic summarization on network Class boundary.

-         Classless protocol (supports VLSM).

-         Have the power to shut the Auto-summarization And make a configured manual Summarization.

-         Default composite metric of bandwidth and delay.

-         You can factor load, MTU and reliability into the metric.

-         Eigrp metric is the same as IGRP*256, It uses the smallest B.W,Reliablity,Load & MTU with the Comulative delay upon the path…..The MTU doesn’t actually used in the Metric calculations, But is included in the EIGRP Routing updates.

-         Sends route updates to multicast address 224.0.0.10, and nei. Reply’s back with   Unicast Address. 

-         Sends non-periodic, partial, and bounded updates.

-         Send Hello packets every 5 sec. and Hold down timer is 15 sec.