Simon Blake wrote:
Taking off my IX hat and plopping on my CDN hat,
I'd observe that during
the Olympics we peaked at around 1.5Gb/s delivery into APE, and about
1Gb/s into WIX. That's on routers with no bilaterals over APE - clearly
somebody is listening to the route servers.
I'm not sure it proves other peers are _really_ listening to the RS' -
just that your streaming return path was via an RS learned path
(although presumably the people hitting those servers got there via the IX).
interested to see any evidence of a widespread practice of overly
strict inbound filtering of routes from APE/WIX/etc, as it would
encourage us to do more bilateral peering.
The StreamingNet routers attached to the exchanges only peer with the
route servers (not for any particular reason, more that until this
discussion started, it hadn't occurred to me to seek bilats - I
hadn't perceived they were necessary). It maybe that folks are allowing
the StreamingNet prefixes and dropping everything else, but that sounds
a little far fetched.
I haven't driven an APE connected router for some years, but it used to
be common. I think I even spoke to you about it once upon a time.
There are engineers who do not like spontaneous traffic swings from
unexpected peers suddenly appearing (particularly when there is a
peering router at or close to the IX, but some smaller sized link back
to the other POP(s)), so choose not to learn or advertise routes
depending on where their traffic load is. I had some particularly
sensitive outbound traffic, so I never used to learn anything off the
RS' except for Citylink/StreamingNet prefixes.
I would from time to time scan the received-routes from the RS' and see
if there was anything I wasn't learning and was interested in, but the
actual occurrence of this was pretty low.
I am sure there are other operators like myself out there...
NB: Some of the assymmetry people are seeing could be from out-of-date
filters, or from the additional route-server ASN in the path causing BGP
to choose a less-desirable path. Not everyone uses the localpref