Network Routing Protocols – IGRP, EIGRP, OSPF, ISIS, BGP

Overview

The aim of routing protocols is to study of accessible routes that exist on the enterprise community, construct routing tables and make routing selections. A number of the most typical routing protocols embrace RIP, IGRP, EIGRP, OSPF, IS-IS and BGP. There are two major routing protocol sorts though many various routing protocols outlined with these two sorts. Hyperlink state and distance vector protocols comprise the first sorts. Distance vector protocols promote their routing desk to all immediately related neighbors at common frequent intervals utilizing lots of bandwidth and are gradual to converge. When a route turns into unavailable, all router tables should be up to date with that new info. The issue is with every router having to promote that new info to its neighbors, it takes a very long time for all routers to have a present correct view of the community. Distance vector protocols use mounted size subnet masks which are not scalable. Hyperlink state protocols promote routing updates solely once they happen which makes use of bandwidth extra successfully. Routers do not promote the routing desk which makes convergence sooner. The routing protocol will flood the community with hyperlink state ads to all neighbor routers per space in an try and converge the community with new route info. The incremental change is all that’s marketed to all routers as a multicast LSA replace. They use variable size subnet masks, that are scalable and use addressing extra effectively.

Inside Gateway Routing Protocol (IGRP)

Inside Gateway Routing Protocol is a distance vector routing protocol developed by Cisco programs for routing a number of protocols throughout small and medium sized Cisco networks. It’s proprietary which requires that you just use Cisco routers. This contrasts with IP RIP and IPX RIP, that are designed for multi-vendor networks. IGRP will route IP, IPX, Decnet and AppleTalk which makes it very versatile for purchasers working many various protocols. It’s considerably extra scalable than RIP because it helps a hop depend of 100, solely advertises each 90 seconds and makes use of a composite of 5 totally different metrics to pick a greatest path vacation spot. Be aware that since IGRP advertises much less often, it makes use of much less bandwidth than RIP however converges a lot slower since it’s 90 seconds earlier than IGRP routers are conscious of community topology modifications. IGRP does acknowledge project of various autonomous programs and routinely summarizes at community class boundaries. As properly there’s the choice to load steadiness site visitors throughout equal or unequal metric value paths.   https://10-0-01.com/

Traits

• Distance Vector

• Routes IP, IPX, Decnet, Appletalk

• Routing Desk Ads Each 90 Seconds

• Metric: Bandwidth, Delay, Reliability, Load, MTU Measurement

• Hop Rely: 100

• Mounted Size Subnet Masks

• Summarization on Community Class Handle

• Load Balancing Throughout 6 Equal or Unequal Price Paths ( IOS 11.0 )

• Replace Timer: 90 seconds

• Invalid Timer: 270 seconds

• Holddown Timer: 280 seconds

• Metric Calculation = vacation spot path minimal bandwidth x delay (usec)

• Break up Horizon

Enhanced Inside Gateway Routing Protocol (EIGRP)

Enhanced Inside Gateway Routing Protocol is a hybrid routing protocol developed by Cisco programs for routing many protocols throughout an enterprise Cisco community. It has traits of each distance vector routing protocols and hyperlink state routing protocols. It’s proprietary which requires that you just use Cisco routers. EIGRP will route the identical protocols that IGRP routes (IP, IPX, Decnet and Appletalk) and use the identical composite metrics as IGRP to pick a greatest path vacation spot. As properly there’s the choice to load steadiness site visitors throughout equal or unequal metric value paths. Summarization is automated at a community class handle nonetheless it may be configured to summarize at subnet boundaries as properly. Redistribution between IGRP and EIGRP is automated as properly. There may be help for a hop depend of 255 and variable size subnet masks.

Convergence

Convergence with EIGRP is quicker because it makes use of an algorithm referred to as twin replace algorithm or DUAL, which is run when a router detects specific route is unavailable. The router queries its neighbors in search of a possible successor. That’s outlined as a neighbor with a least value path to a selected vacation spot that does not trigger any routing loops. EIGRP will replace its routing desk with the brand new route and the related metric. Route modifications are marketed solely to affected routers when modifications happen. That makes use of bandwidth extra effectively than distance vector routing protocols.