[address-policy-wg] 2023-01 New Policy Proposal (Reducing IXP IPv4 assignment default size to a /26)

Hi,

>>> Assignments strictly larger than a /24 will only be made to IXPs that
>>> offer the exchange of IPv4 routing information over IPv6 at their
>>> route servers
>> 
>> As far as I understand, this protocol is not widely deployed in IXPs,
>> nor is it widely tested in inter-AS production environments. It would be
>> concerning if an untested protocol were mandated as a production
>> requirement in a RIR addressing policy document.
>> 
>> Before continuing down this path, could the authors provide information
>> on how this protocol works in production environments?
> 
> This part of the proposal is intended to foster the adoption of the technology.
> IXPs may offer it as beta or experimental while still doing the actual exchange
> of traffic via standard BGP over IPv4.

Doesn’t the way this policy is written defeat the purpose of using IPv6 to exchange IPv4 routing information? Only those who can use IPv6 (and arguable therefore don’t need IPv4 anymore) can get more IPv4 space…

> We are aware this is part controversial; we can remove it if the community thinks
> this is a bad idea.

Putting controversial stuff is address policy is usually not a good idea. In my opinion address policy has to provide what is needed for a super stable environment. Enforcing the use of less tested or experimental protocols doesn’t fit with that.

Now, I totally understand the chicken and egg problem here: as long as IXPs get IPv4 addresses there will be no need to exchange IPv4 routing information over IPv6. But until that has been properly tested we continue to give them IPv4 space. But let’s not put in artificial restrictions to make them test it. If the real reason is that we don’t have enough IPv4 space to give to IXPs in the future, then let’s make *that* clear.

Like: “From <insert-cutoff-date-here> IXPs will no longer be able to grow their IPv4 assignment beyond <insert-prefix-size-here>. IXPs that anticipate needing to grow larger than this are strongly encouraged to start testing with exchanging IPv4 routing information over IPv6”.

The cutoff date may be a little arbitrary (I’m sure the NCC can give reasonable predictions to base it on) but at least it matches with reality :)

Cheers,
Sander