The Enhanced Interior Gateway Routing Protocol (IGRP) represents an evolution from its predecessor IGRP (refer to Chapter 38, "Interior Gateway Routing Protocol)." This evolution resulted from changes in networking and the demands of diverse, large-scale internetworks. Enhanced IGRP integrates the capabilities of link-state protocols into distance-vector protocols. It incorporates the Diffusing-Update Algorithm (DUAL) developed at SRI International by Dr. . Garcia-Luna-Aceves. | Enhanced Interior Gateway Routing Protocol EIGRP Documentation HOME CONTENTS PREVIOUS NEXT GLOSSARY FEEO ACK SEARCH HELP Table of Contents Enhanced IGRP Background Enhanced IGRP Capabilities and Attributes Underlying Processes and Technologies Routing Concepts Neighbor Tables Topology Tables Route States Route Tagging Enhanced IGRP Packet Types Enhanced IGRP Background The Enhanced Interior Gateway Routing Protocol IGRP represents an evolution from its predecessor IGRP refer to Chapter 38 Interior Gateway Routing Protocol . This evolution resulted from changes in networking and the demands of diverse large-scale internetworks. Enhanced IGRP integrates the capabilities of link-state protocols into distance-vector protocols. It incorporates the Diffusing-Update Algorithm DUAL developed at SRI International by Dr. . Garcia-Luna-Aceves. Enhanced IGRP provides compatibility and seamless interoperation with IGRP routers. An automaticredistribution mechanism allows IGRP routes to be imported into Enhanced IGRP and vice versa so it is possible to add Enhanced IGRP gradually into an existing IGRP network. Because the metrics for both protocols are directly translatable they are as easily comparable as if they were routes that originated in their own Autonomous Systems ASs . In addition Enhanced IGRP treats IGRP routes as external routes and provides a way for the network administrator to customize them. This chapter provides an overview of the basic operations and protocol characteristics of Enhanced IGRP. http univercd cc td doc cisintwk ito_doc 1 of 5 5 6 2001 3 52 24 PM Enhanced Interior Gateway Routing Protocol EIGRP Enhanced IGRP Capabilities and Attributes Key capabilities that distinguish Enhanced IGRP from other routing protocols include fast convergence support variable-length subnet mask support for partial updates and support for multiple network-layer protocols. A router running Enhanced IGRP stores all its neighbors routing tables .
