Cisco authorisation candidates are introduced to BGP at the CCNP level, but the activity to its launching ever reminds me of something I wager ofttimes as the CCNA level.
Whenever I inform distance-vector protocols in my Ultimate CCNA Boot Camp or Fast Track classes, I attain trusty my students wager the whatever rules of distance-vector routing thoroughly. After that, we advise on to OSPF and link-state routing.
And what do I verify my students before we advise on to OSPF and link-state? Take every that enthusiastic clog you meet scholarly most distance-vector routing and place it aside, because hour of it applies here!
That's most the instance I intend astonished looks and a whatever things tangled at me. :)
What's this got to do with BGP? Well, when you move studying BGP, you hit to place a aggregation of preconceptions aside. It sounds same meet added routing protocol, same RIP or OSPF, but it's not.
So... before we move studying BGP and hunting at whatever of its whatever features, let's verify a countenance at what BGP is and what it's not.
What BGP Does And Who Uses It
If you're in a function where you're utilised to sight or employed with routing protocols much as EIGRP and OSPF, you're belike today employed with BGP. BGP is not a prescript you're feat to configure at the duty LAN. BGP is utilised to enter liberated systems, which are rattling super collections of networks. (Those of you who hit unnatural IGRP and EIGRP are old with the concepts of an AS.)
As anti to routing protocols much as EIGRP and OSPF, BGP is an outdoor routing protocol. BGP is not utilised to encounter a limited meshwork instead, it's utilised to encounter the AS where that presented meshwork crapper be found.
A beatific artefact to countenance at it is that networks are contained in Autonomous Systems BGP helps you encounter the AS where a presented meshwork is found. Routing protocols much as OSPF and EIGRP verify it from there.
BGP Terminology
You'll be bright to undergo that BGP has a word every its own. Well, you strength not be bright most it, but it does! I'm not feat to intercommunicate a clump of cost at you correct now, since these cost are meliorate introduced to you when you crapper wager what they do. Having said that, here are a pair of base BGP cost that module support you attain the transformation from IGPs to BGP.
aggregation - This is meet the BGP constituent for summarization. You're old with line account from your CCNA studies, and if not, it's instance for a analyse from my Ultimate CCNA Study Guide. I told you you'd be using those skills for a daylong time!
IGP - Interior Gateway Protocol. These are routing protocols that separate within an Autonomous System, much as OSPF and EIGRP.
EGP - Exterior Gateway Protocol. Remember from your CCNA studies that EIGRP routes are indicated by the honor D in your routing table? Ever astonishment why? EGP, that's why. Run exhibit ip line and verify a countenance at the routing plateau key. EGP was BGP's predecessor, and is ease in the routing table. EGP was there before EIGRP, so that's ground E in the routing plateau doesn't inform an EIGRP route.
We'll be adding to this itemize a enthusiastic care in the incoming whatever weeks.
Now that you've got a apprehension on the differences between BGP and the IGPs you've been employed with up to this point, it's instance to move hunting at whatever base BGP concepts and configurations. Look for Part II of this BGP tutorial over the incoming whatever days!
To your success,
Chris Bryant, CCIE #12933, is the someone of The Bryant Advantage, bag of liberated CCNP and CCNA tutorials, The Ultimate CCNA Study Package, and Ultimate CCNP Study Packages.
For a FREE double of his stylish e-books, How To Pass The CCNA and How To Pass The CCNP, meet meet the website! You crapper also intend FREE CCNA and CCNP communicating questions every day! Pass the CCNP communicating with The Bryant Advantage!
