RE: BGP question

Guyz correct me if im wrong ..

Whenever a router receives an update about destination from an IBGP peer, the
router tries to verify internal reachability for that destination before
advertising it to eBGP peers.

This check makes sure that transit routes which are not running BGP can carry
transit traffic.

Usually Transit Routers must run iBGP. If they are running iBGP then
synchronization can be
disabled (it is actually disabled by default since i guess 12.2.T). But that
implies that
all iBGP routers must have full mesh connectivity because iBGP doesnot have
any loop prevention mechanism like AS-PATH, thus a route that is received from
an iBGP peer is not advertised to another iBGP peer.

An alternative to full-mesh iBGP are Route Reflector and Confederations .

For detail explanation refer to TCP/IP Volume II by Jeff Doyle and Internet
Routing Architectures by Sam halabi

Regards
Zeeshan

> Date: Mon, 6 Apr 2009 09:48:46 -0400
> Subject: Re: BGP question
> From: all.from.nj_at_gmail.com
> To: omar.maiah_at_gmail.com
> CC: ccielab_at_groupstudy.com
>
> Hello,
>
> If possible, might be best to purchase a VOD of some sort to hear the
> discussions of BGP operations. If you can get to Cisco Live (networkers)
> then this is a good chance to get a lot of good info in a short amount of
> time.
>
>
> Here are some links which will help as well.
>
> BGP Technology:
>
http://www.cisco.com/en/US/tech/tk365/tk80/tsd_technology_support_sub-protoco
l_home.html
>
> Would suggest you to consult this Q&A section, it is good:
>
http://www.cisco.com/en/US/tech/tk365/technologies_q_and_a_item09186a00800949
e8.shtml
>
> From this link, here is the question regarding sync:
>
http://www.cisco.com/en/US/tech/tk365/technologies_q_and_a_item09186a00800949
e8.shtml#nineteen
>
> HTH,
>
> Andrew Lee Lissitz
>
>
>
>
> On Mon, Apr 6, 2009 at 9:32 AM, <omar.maiah_at_gmail.com> wrote:
>
> > I have a question regarding BGP, we know about the synchronization
problem,
> > but is there a BGP split horizon rule, and if so what is it ? whats the
> > difference between BGP split horizon and synchronization ? and what about
> > confidereation and route reflectors, they are a solution to which of them
?
> >
> >
> > Blogs and organic groups at http://www.ccie.net
> >
> > _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
> >
> >
> >
> >
> >
> >
> >
> >
>
>
> --
> Andrew Lee Lissitz
> all.from.nj_at_gmail.com
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
>
>
>
>
>
Received on Mon Apr 06 2009 - 08:42:26 ART