Re: Calling LinkedIn, Amazon and Akamai @ DE-CIX NY

[Julien Goodwin <nanog () studio442 com au>]

On 31/1/19 7:08 pm, Mark Tinka wrote:
> I believe most exchange points maintain both route servers and route
> collectors.
>
> Generally, most peers will connect to the RS, but not all. As you
> mention, some may connect but not send any routes.
>
> However, I believe all peers will connect to the RC. Of course, I can
> envisage scenarios where even this could be selectively done. But the
> reasons for (not) connecting to the RC are very different from those for
> (not) connecting to the RS.

Back when I looked more deeply at this (mid-2014 when I was redoing the
AS15169 policy around this area) I saw things rather differently, and my
impression is little has changed since.

Even in exchanges that strongly encourage their use route collectors
were much less connected to than route servers, and few exchanges had
them in the first place.

Part of the problem with advertising on route servers is many clients,
including networks that should know better often treat those routes as a
higher priority than is sensible, in some cases equal or higher than a
PNI link in the same city.

Yes we could have used prepends, but that's not necessarily effective
and affects everyone for the actions of a few, and is why the routes
AS15169 advertised on route servers reduced back then.