cogent bgp filtering policies?

John van Oppen john at
Sun Jul 27 23:47:21 UTC 2008

That software might be a good solution for sending them updates, heck a
script sending it out every time it detects an update might also cause
them to get more excited about automating updates.   ;)   We also had
issues with them wanting a paper (or faxed) LOA which seemed a bit
onerous given the number of prefixes we announce.

The le 24 matches should have been easy since the reason we wanted them
were because we have customers using their own ASNs to announce
sub-allocations of our space, a quick look on their part the first time
we made the request would have shown that the sub allocations were all
originated from downstream ASNs from our network.   

If anyone has an engineering contact at cogent (ie not the support
contact) I would love to talk to them as it seems support department
front-end is the problem and not necessarily cogent's actual policies.


John van Oppen
Spectrum Networks LLC
206.973.8302 (Direct)
206.973.8300 (main office)

-----Original Message-----
From: Paul Wall [mailto:pauldotwall at] 
Sent: Sunday, July 27, 2008 4:30 PM
To: John van Oppen
Cc: nanog at
Subject: Re: cogent bgp filtering policies?

Cogent does not support IRR.  Since you're using IRR yourself, Richard
Steenbergen's IRRPT ( has a script called 'irrpt_nag'
which is good for sending automated requests for prefix-list updates
with providers that continue to process them manually.

You can (and should) ask that Cogent's "Engineering" department okay
you for support for de-aggregation down to the /24 level or more
specific.  They will with proper justification or a general feeling
that you've got good reason and aren't just looking to gratuitously
de-aggregate prefixes for no reason.

Drive Slow,

On Sun, Jul 27, 2008 at 5:59 AM, John van Oppen <john at>
> Now that I am on my third round of an email argument with cogent's
> support department about adding prefixes to our filters (and them not
> understanding why I want le 24 matches on the blocks from which we
> allocate subnets to multi-homed customers) I figure it would be a good
> idea to ask if anyone has ever gotten cogent to setup any IRR based
> filtering on a customer connection.
> We are a small-ish regional transit provider in the northwest
>> 100 prefixes and just spent the last few days writing emails and
> calling trying to get cogent to accept more than 30% of the routes we
> were announcing.    We have IRR (radb to be specific) filters set up
> with our other four providers which really lowered my tolerance for
> having to go round and round to get prefixes added.   Heck, at this
> point I would settle for a direct email address for their engineering
> department just to avoid the arguments with the support monkeys.
> I should note that this is actually the second time I have had this
> issue (the last time was with one of our customers and their cogent
> connection) even though we only turned up our service recently.
> John van Oppen
> AS11404

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