Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

EIGRP and IGRP lab


I finished a CCNA course and managed to setup at home a small OSPF network, then moved onto a EIGRP network and all worked, however I have noticed we missed the IGRP routing protocol on the course. Is this just the same as EIGRP but internal on a LAN?


Re: EIGRP and IGRP lab


IGRP is the older version for EIGRP. IGRP is a true distance Vector Protocol where as EIGRP is a hybrid protocol bringing the advantages of both models ( Link State and Distance Vector) into 1 protocol.

Here are some of the comparisons :-

# Both are Cisco Proprietary protocols.

# Both have same logic for equal cost paths.

# IGRP and EIGRP path selection is based on Bandwidth/Delay metric. Using some EIGRP commands maximum bandwidth can be changed as required while in IGRP it cannot be changed.

# Both have same metric accumulation, if divide the EIGRP metric by 256.

# EIGRP has fast convergence time while IGRP has a slow convergence time.

# IGRP sends full routing table during update while EIGRP does not.

# IGRP requires Distance Vector loop avoidance features while EIGRP does not.

# EIGRP uses Dual algorithm while IGRP uses Bellman and Ford algorithm.

# IGRP send periodic routing updates every 90 seconds while EIGRP send triggered change-based updates when there is a topology change has occurred.

I beleive that it has also been removed from the exam as it is being removed from new IOS versions aswell.