Re: Can an IXP sell IP transit?

[Bill Woodcock <woody () pch net>]

> On Nov 5, 2024, at 00:56, William Herrin <bill () herrin us> wrote:
> On Mon, Nov 4, 2024 at 8:44 AM Douglas Fischer <fischerdouglas () gmail com> wrote:
> > But I have seen a reasonably large scenario in which the IXP operator,
> > maintaining the MLPA LAN with the pair of Route-Servers, adds
> > another participant with the SAME ASN as the route-servers,
> > and through this participant starts to sell traffic.
>
> Of course they can sell transit. The reason they don't is that it has
> the potential to create a conflict of interest. When your customer is
> also a competitor and your customer suffers an outage that's your
> fault... Well, you see where this is going.

Yep.  Other-Bill has this exactly right.  To add a little to that, for an IXP to be successful, many ISPs have to trust 
it enough to build out to it and participate in it, which requires investment on their parts.  To be trustworthy, it 
helps a _lot_ if the IXP is “neutral.”  That is, it’s not a part of your competitor, and you have reason to believe 
that if you invest in it now, it won’t treat you unfairly in the future.

So, to succeed, it helps a _lot_ if IXP have very simple, unitary models.  They don’t do other things which makes them 
complicated, opaque, hard-to-understand, hard-to-trust.  Just not handling money at all is a huge win for IXP stability 
and growth, for instance, because it simplifies things and makes them more easily trusted.

Selling transit is a thing that ISPs do.  When an IXP competes with its ISP participants, it not only sets itself up 
for the conflicts and failures that Bill points out, it also makes itself less trustworthy, because of the _future 
risk_ of those conflicts and failures, and that decreased trustworthiness decreases “investor confidence” and ISP 
willingness to extend themselves, and that, in turn, causes the IXP to not grow, or grow more slowly than it would 
otherwise.

                                -Bill