CloudFlare IPv6 BGP announcements - WTF guys?

Jared Mauch jared at
Tue Jul 17 15:38:15 CEST 2012

On Jul 17, 2012, at 9:21 AM, Sascha Luck wrote:

> On Tue, Jul 17, 2012 at 08:53:24AM -0400, Jared Mauch wrote:
>> I think the issue here is people that feel entitled to pollute a global
>> network of routers, etc and impose their policy upon my network.
> I'm working on the assumption that some operators do this out of
> operational necessity, not stupidity or "because they can"
> Like all assumptions, it is probably flawed.

I suspect it may be.  I've come to learn in my recent departure from backbone engineering that companies can't even enumerate their IP address assets.  This is a foreign concept to me entirely, but its far too common.  I've also observed that most people can't configure BGP properly and it results in a significant number of routing table leaks.  These are things that could be easily solved, but the vendors are unwilling to make the necessary changes to improve the situation.

>> There are community driven models of this, through the RIR.  Keeping
>> IPv6 table growth reasonably by complying with these policies isn't
>> that hard.  I think that's the problem that myself and others see here.
>> If you feel entitled to announce a few /64's or /128's to your ISP and
>> they accept them, then great.  That doesn't mean they are globally
>> reachable.
> I've no problem with using PIv6 or indeed separate /32 PAv6 for such purposes either, provided the RIR policies allow for such use. This may well be the best compromise.

Nor do I.

>> CloudFlare may have legitimate reasons for doing what they are here.
> I've seen more deaggregated announcements lately, often connected to some kind of business continuity / disaster recovery service. I don't like it either but it suggests there is a genuine need that
> policy doesn't recognize right now.

If you buy all your services from $carrierX and those announcements are there for business continuity then great.  You should also announce the aggregate someplace, or have them do it.

>> lawn/routing table" but there are real costs of these entries in the
>> RIB + FIB.  I would rather not see a model where you're billed based on
>> your pollution, but that was the Sean Doran model of "send me a check"
>> for use of my FIB entry.  I can assign a cost to it, can you?
> I don't like that argument. IMO it plays into the hands of the ITU and
> certain large operators where "termination fees" "per-ASN-billing" and "pay to play" are certainly on the wish list. I can't see a solution either though. In the short term, allowing the
> use of PIv6 for this purpose might help keeping it under control.

Nor do I.  But its possible to assign a cost.  Since a device like Cisco7600/6500 can have 256k IPv6 entries by default, I can take the cost of that fully populated chassis and divide by 256k.  Multiply by number of devices in network and you start to get that cost for a simple recovery number, let alone one you can manage and have profit from.  Some devices are inexpensive, some those slots are very valuable.  I am waiting to see a few scaling walls be hit in the IPv4 world.  It's coming soon, when global routes + internals start to reach 512k I expect to see some carriers have trouble.

	- Jared

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