Interior Gateway Routing Protocol
- Interior Gateway Routing Protocol
Interior Gateway Routing Protocol (IGRP) is a kind of IGP which is a distance-vector routing protocol invented by Cisco, used by routers to exchange routing data within an autonomous system.
IGRP is a proprietary protocol. IGRP was created in part to overcome the limitations of RIP (maximum hop count of only 15, and a single routing metric) when used within large networks. IGRP supports multiple metrics for each route, including bandwidth, delay, load, MTU, and reliability; to compare two routes these metrics are combined together into a single metric, using a formula which can be adjusted through the use of pre-set constants. The maximum hop count of IGRP-routed packets is 255 (default 100).
IGRP is considered a classful routing protocol. Because the protocol has no field for a subnet mask, the router assumes that all interface addresses within the same Class A, Class B, or Class C network have the same subnet mask as the subnet mask configured for the interfaces in question. This contrasts with classless routing protocols that can use variable length subnet masks. Classful protocols have become less popular as they are wasteful of IP address space.
Advancement
In order to address the issues of address space and other factors, Cisco created EIGRP (Enhanced Interior Gateway Routing Protocol). EIGRP adds support for VLSM (variable length subnet mask) and adds the Diffusing Update Algorithm (DUAL) in order to improve routing and provide a loopless environment. EIGRP has completely replaced IGRP, making IGRP an obsolete routing protocol. In Cisco IOS versions 12.3 and greater, IGRP is completely unsupported. In the new Cisco CCNA curriculum (version 4), IGRP is mentioned only briefly, as an "obsolete protocol".
External links
* [http://www.cisco.com/warp/public/103/5.html Cisco - An Introduction to IGRP]
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Interior Gateway Routing Protocol — (IGRP) est un protocole de routage classful de type IGP à vecteur de distance créé par Cisco et utilisé par les routeurs pour échanger leurs tables de routage dans un système autonome. IGRP a été créé en partie pour remédier aux limitations de… … Wikipédia en Français
Interior Gateway Routing Protocol — Este artículo o sección necesita referencias que aparezcan en una publicación acreditada, como revistas especializadas, monografías, prensa diaria o páginas de Internet fidedignas. Puedes añadirlas así o avisar … Wikipedia Español
Interior Gateway Routing Protocol — Das Interior Gateway Routing Protocol (IGRP) ist ein in den 1980er Jahren von Cisco entwickeltes proprietäres Distance Vector Routingprotokoll, das von Routern eingesetzt wird, um innerhalb eines autonomen Systems Routing Informationen… … Deutsch Wikipedia
Interior Gateway Routing Protocol — Abbreviated IGRP. A distance vector routing protocol from Cisco Systems for use in large heterogeneous networks. See also heterogeneous network … Dictionary of networking
Enhanced Interior Gateway Routing Protocol — (EIGRP) is a Cisco proprietary routing protocol loosely based on their original IGRP. EIGRP is an advanced distance vector routing protocol, with optimizations to minimize both the routing instability incurred after topology changes, as well as… … Wikipedia
Enhanced Interior Gateway Routing Protocol — Das Enhanced Interior Gateway Routing Protocol (EIGRP) ist ein 1992 von Cisco veröffentlichtes proprietäres Routing Protokoll. Bei EIGRP handelt es sich um eine verbesserte Version des früheren IGRP, zu welchem weiterhin Kompatibilität besteht.… … Deutsch Wikipedia
Enhanced Interior Gateway Routing Protocol — Abbreviated EIGRP. A proprietary link state distance vector routing protocol from Cisco, first released in 1994. EIGRP improves performance by using information derived from distance vector protocols, but also includes an algorithm for… … Dictionary of networking
Enhanced Interior Gateway Routing Protocol — (EIGRP) est un protocole de routage développé par Cisco à partir de leur protocole original IGRP. EIGRP est un protocole de routage hybride IP, avec une optimisation permettant de minimiser l instabilité de routage due aussi bien au changement de … Wikipédia en Français
Interior gateway protocol — An interior gateway protocol (IGP) is a routing protocol that is used within an autonomous system.In contrast an exterior gateway protocol is for determining network reachability between autonomous systems (AS) and makes use of IGPs to resolve… … Wikipedia
Routing protocol — A routing protocol is a protocol that specifies how routers communicate with each other to disseminate information that allows them to select routes between any two nodes on a network. Typically, each router has a prior knowledge only of its… … Wikipedia
