[c-nsp] Conditional advertise-map

[Heath Jones]

Gert,

Yes, you are correct about the community to 36997 if they offer it and have
implemented their preferences accordingly on all external sessions. I know a
lot of ISP's don't do it / only do it with peering & major upstreams.

You will probably find that the as path prepending will chew more memory
than 1 more prefix matching an existing as path so the subnetting option
works out better.

I can see the problem with routing tables getting bigger, I can also see
that the bigger vendors are charging a huge amount of cash for routers
needed to maintain even a few tables. My suggestion is hardly - as you
suggest - careless. You really don't need to gripe at me about that - thats
just not cricket. I'm just trying to help him out with some suggestions. It
would turn 1 prefix into 2 - thats hardly unreasonable..

Heath



On 15 September 2010 17:19, Gert Doering <gert at greenie.muc.de> wrote:

> Hi,
>
> On Wed, Sep 15, 2010 at 03:38:17PM +0100, Heath Jones wrote:
> > Also, I can see from global bgp they are not peering with eachother so
> its
> > not a situation where communities could help.
>
> If 36997 would offer a "make it worse than peering/upstream" community,
> of course it would help.
>
> > The other solution is to
> > advertise a supernet to 36997 and break this in half and advertise both
> > subnets to 5511 (assuming you have a decent sized prefix >/24).
>
> If you had to pay the money for the router upgrades just to handle the
> ever-growing BGP tables, I bet you were more careful about suggesting
> deaggregation...
>
> gert
> --
> USENET is *not* the non-clickable part of WWW!
>                                                           //
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> Gert Doering - Munich, Germany
> gert at greenie.muc.de
> fax: +49-89-35655025
> gert at net.informatik.tu-muenchen.de
>