Alright gang, 3rd time through the entire tutorial, and understood most of it. Don't know it like I know the back of ...hey where the hell did my hand go? ;-) Ref: http://ww.cisco.com/warp/public/459/14.html also known as Part 2 Tutorial of BGP4 Case Studies Synchroniztion... Calling all BGP4 gurus. Just when you thought you understood the BGP4 basics, you start thinking outside the box! Something the case study doesn't really expand on is: Are most of the Internet core routers running BGP4 w/ NO SYNCHRONIZATION? Or are they running with NEXT-HOP-SELF when talking to external ASes. {boy that's too close to Asses if you ask me.}???? Assumption: if you don't know how to get to the NEXT-HOP you drop the route {if you don't have a route in your IGP table}. Example to follow, which may or may not clearify my confusion: 99.99--(100) AA 1.1--1.2 (200) BB 2.1-- {next line} --2.2 (300) CC 3.1--3.2 (400) DD--88.88 Where AA is the router designation, (.*) is the AS, and ?.? is just the network addresses. So, with SYNCH. on by default: 1. Router AA will tell Router BB that 99.99 is reachable via 1.1 2. Router BB will add the route for 99.99 because it knows how to get to 1.1; either through the network statement, or static. 3. Router BB will pass the route 99.99 on to Router CC with the NEXT-HOP being 1.1. Router CC has no clue about where network interface 1.1 is, and will drop the route. 4. Router CC turns off synch {NO SYNCHRONIZATION} and will accept the route. But I am still not sure how Router CC will pass on the packet...??? OR Router BB will pass the route 99.99 on to Router CC with the NEXT-HOP-SELF statement, in which case Router CC will say "OK dude! If I want to get to network 99.99 I will send it to 2.1" 5. And then does Router CC also have to send route 99.99 to Router DD with NEXT-HOP-SELF because Router DD doesn't have a clue about 2.1? OR or else, Router CC sends 99.99 on to Router DD with the NEXT-HOP-SELF statement, in which case Router DD will also say "Right on dudette! If I want to get to network 99.99 I will send it to 3.1." Correct me if I have missed any points. Don't go soft, as I am really trying to wrap my beer cells around this thing! Thanks ahead of time, and looking forward to your responses! Troy C p.s. Hey, at least it wasn't "How many questions are on the CCNA v.1?" p.s.s. Did any one else catch the error in section 3? http://www.cisco.com/warp/public/459/15.html In the _Use of set as-path prepend Command_ 2nd paragraph should state: ...in AS600 will have network reachablity information about 170.10.0.0 via two..... Does Cisco update these? Should I shoot them an E about it? ___________________________________ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
