Re: CIDR FAQ

[Nicolas Williams <nmw () news ios com>]

Dave Siegel previously wrote:

> > As I recall the original discussion was of colocating a router, to forward
> > packets, with a workstation, to compute routes.

> So what would the normal implementation of such a design be?  ebgp-multihop
> all of your peers into the PC, and then a single peering session the Cisco,
> presuming no "next-hop-self" routes?

No. Colocated BGP4 "proxies" (I'm still not sure what to call these,
anyone?) would peer via EBGP with other ASes BGP4 "proxies" on the same
net. The next_hop BGP4 attribute on all routes exchanged would be that
of the routers on the high speed interconnect, not of the "proxies."
ASes that do not implement this would still peer via EBGP
router-to-router as usual and would not see the "proxies;" eventually
everyone would move towards having "proxies" or else router vendors
would beef up their products, either way, we're all happy.

> I can see some amount of value in such a design, if it could be made to work
> correctly.  Does anybody have the spare equipment to build a lab?  (pfeh, yeah,
> right)

It would work (see the comment on the next_hop BGP4 attribute above).

I'm sure there are folk out there that would be willing to experiment,
all you need is for two ASes to try it at some exchange (and permission
by the exchange to run the necessary ethernet).

> Dave
>
> -- 
> Dave Siegel                    Director of Engineering, Net99
> http://www.webcity.com/                (602)249-1083 24x7 NOC line
> http://www.rtd.com/~dsiegel/   (520)318-0696 My Tucson Office


Nick