* Angela Dall'Ara
A new RIPE Policy Proposal, 2023-01, "Reducing IXP IPv4 assignment default size to a /26" is now available for discussion.
The goal of this proposal is to extend the lifetime of the IXP IPv4 address pool and to motivate IXPs to implement the exchange of IPv4 routing information over IPv6.
Hi, This proposal is a step in the right direction, although I feel it should have gone further. I've already elaborated on why in the «IXP pool lower boundary of assignments» thread, so I don't seek to re-hash that whole thread, but for the record I'll repeat the gist of it in the formal proposal thread: Since IPv4 is a finite resource that needs to last "forever", it seems wasteful to willfully assign too large prefixes to IXPs that do not need them. According to https://github.com/mwichtlh/address-policy-wg, a /26 would be excessively large for a majority of IXPs. I would rather see a policy that did not specify a default size at all, but rather instructed the NCC to right-size each assignment according to the "at least 50% utilisation after a year" rule. Note that this should not be considered an objection to this proposal, as I mentioned before it is a step in the right direction, after all. With that out of the way, I have a few questions/comments: 1) Regarding «New IXPs will be initially assigned a /26 by default. Upon request, a /25 can be assigned initially. If the initial assignment has been utilised by at least 50%, IXPs can request the assignment of a /24»: This is somewhat difficult to decipher. Does it mean that: a) a new IXP can simply ask for an initial /25 and receive it, no questions asked? b) an existing IXP that has used 50% of an initial /26 will be able to upgrade straight to a /24, i.e., bypassing a /25? (Or even %50-of- /27→/24, in an unlikely but not impossible corner case.) To improve clarity, I would suggest not to mix the conditions for new IXPs / initial assignments with the conditions for already existing IXPs that seek to upgrade a previous assignment. 2) Regarding «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»: a) What is the purpose / meaning of the word «strictly» here? I assume it is there for a reason, but removing it does not seem to me to change the meaning of the sentence in any way (but then again, I am not a native English speaker). b) Depending on whether one considers an assignment from the NCC to the IXPs as to be a continuous state or as a one-time event, this may cause an instant obligation on current holders of larger-than-/24 IXP prefixes to implement IPv4-over-IPv6 routing in their route servers. Is that the intention? Tore