From: Eric R. (epr01@pacbell.net)
Date: Tue Nov 12 2002 - 00:13:09 GMT-3
That is one kind of problem that arises from having greater than a /21.
Yeah, your directly connected ISP's will take your $$$ and advertise
your /whatever, but that doesn't mean everyone will accept it
downstream. If I'm NOT an ISP but multi-homed do I want my router filled
with upteen thousand /24's, No! An ISP is designed to absorb somewhat
bgp route's flapping but my Enterprise links don't need to be filled
with BGP route's flapping. Those links cost me big $$$. Don't think for
one moment that having 50,000 ma and pa shops advertising /24's around
the world there would not be considerable flapping. I mean doesn't
advertising all these /24's defeat the purpose of aggregation, which is
suppose to clam the internet and BGP route flapping.
This would make a good nanog thread ;-)
----- Original Message -----
From: "Paul Jin" <pauljin@yahoo.com>
To: "MADMAN" <dave@interprise.com>; "Hamele Kassa" <hkassa@attrmc.net>
Cc: "Brian T. Albert" <brian.albert@worldnet.att.net>;
<ccielab@groupstudy.com>
Sent: Monday, November 11, 2002 5:04 PM
Subject: Re: BGP & multihoming
> I cannot remember who it was for sure, but I had a situation where I
got for
> a customer of ours, to advertise a customer owned /24 to ATT and they
had no problems.
>
> Everything went fine, and a week or two later, I got a call from the
customer saying
> there is a particular web site that the executive members needed to
get to but somehow they could not since the change over to ATT.
>
> What we found out was the fact that although ATT took in the /24
prefix and readvertised it, there was an ISP few hops down that did not
accept /24. and the
> web server that the customer needed to get to was behind that ISP.
>
> But I cannot remember who it was, and this was back in early part of
2001.
>
> Has anyone had any similar experience?
>
> - Paul
>
> MADMAN <dave@interprise.com> wrote:I keep seeing people refer to
this /19 as the smallest aggregate that
> will be accepted by a provider though I have yet to meet this provider.
> I have set up several customers with dual home full routes and they
> announce a single /24 network or maybe a couple but very few have /19 or
> better. The providers I have worked with that accepted the /24 include
> Qwest, MCI, Sprint, Onvoy, and AT&T come to mind.
>
> Dave
>
> Hamele Kassa wrote:
> >
> > Brian,
> >
> > You do not need to secure your own registered address/es(your
network has to
> > be bigger than /19 space to qualify). The IP address/es assigned to you
> > from your providers (/24 or shorter address space) will work for you as
> > long as you are running BGP(no longer prefix than /24). However you
need to
> > secure and AS from ARIN(if you are multihomed you will qualify).
> >
> > I hope this helps.
> >
> > HK
> >
> > ----- Original Message -----
> > From: "Brian T. Albert"
>
> > To: "MADMAN"
> > Cc:
> > Sent: Sunday, November 10, 2002 10:51 AM
> > Subject: RE: BGP & multihoming
> >
> > > When you say "your own registered address/es", do you mean prefixes
> > assigned
> > > to you from your 2 providers or obtained from another authority? What
> > other
> > > authority can assign you prefixes independent of you providers,
and what
> > are
> > > the requirements to obtain them?
> > >
> > > BA
> > >
> > > -----Original Message-----
> > > From: MADMAN [mailto:dave@interprise.com]
> > > Sent: Saturday, November 09, 2002 9:12 PM
> > > To: Brian T. Albert
> > > Cc: ccielab@groupstudy.com
> > > Subject: Re: BGP & multihoming
> > >
> > >
> > >
> > > You don't need NAT if you have your own registered address/es. No
> > special
> > > config required, you simply announce your public address/es
> > >
> > > Dave
> > >
> > > "Brian T. Albert" wrote:
> > >
> > > > In the real world can BGP multihoming to 2 different providers be
> > > > accomplished without NAT for the internal networks? I have
found some
> > > links
> > > > on CCO http://www.cisco.com/warp/public/459/BGP-PIX.htm that
show how to
> > > do
> > > > it with NAT, but is it possible without. If so, can someone
supply some
> > > > config examples or good links.
> > > >
> > > > Thanks
> > > >
> > > > Brian T. Albert
> > > > brian.albert@worldnet.att.net
> > >
> > > --
> > > David Madland
> > > CCIE# 2016
> > > Sr. Network Engineer
> > > Qwest Communications Inc.
> > > 612-664-3367
> > > dave@interprise.com
> > >
>
> --
> David Madland
> CCIE# 2016
> Sr. Network Engineer
> Qwest Communications
> 612-664-3367
>
> "You don't make the poor richer by making the rich poorer." --Winston
> Churchill
This archive was generated by hypermail 2.1.4 : Tue Dec 03 2002 - 07:22:57 GMT-3