Cogent input

Justin Shore justin at
Thu Jun 11 22:37:45 UTC 2009

Tore Anderson wrote:
>> advertise loopbacks, and another for the actual feed. The biggest
>> issue we have with them is that they don't allow deaggregation. If
>> you've been allocated a prefix of length yy, they'll accept only
>> x.x.x.x/yy, not x.x.x.x/yy le 24. Yes, sometimes deaggregation is 
>> necessary or desirable even if only temporarily.
> Interesting.  I requested exactly that when filling in their BGP
> questionnaire, and they set it up - no questions asked.

It would be a show-stopper for us if they didn't let us deaggregate. 
We're not really wanting their service for our existing service area. 
We're wanting to use it to expand to a new service area that is only 
connected by a much lower-speed service back to the bulk of our current 
network for specific services like voice.  Our PI space is currently 
broken up to 1) let us effect some measure of load-balancing with Cox 
(any prefixes we advertised out Cox instead of our much larger tier-1 
resulted in a wildly disproportionate amount of preference given to Cox; 
not sure why) and 2) let this new venture get started with a 
reasonably-sized allotment of IP.  It will be advertised out local 
providers in that area and also at our main peering point with 
significant prepending.  Visa versa for our other prefixes.  We have to 
deaggregate a little bit to make this work (but not excessively of course).

> I have been promised, in writing, that they will provide us with native
> IPv6 transit before the end of the year.

I hope at least some SPs make this commitment back in the states.  I 
can't find any tier-1s that can provide us with native v6.  Our tier-1 
upstream has a best effort test program in place that uses ipv6ip 
tunnels.  The other upstream says that they aren't making any public 
IPv6 plans yet.  It's hard to push the migration to v6 along when native 
v6 providers aren't readily available.


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