I've read this draft. I don't have a strong opinion on the proposal per se, but have a couple of minor comments:
1. In Section 4, the draft says: However, Subnet-router anycast address has not been implemented and in practice, this has not been a problem. I'm afraid "has not been implemented" is too strong. In fact, we have "implemented" it in the KAME/BSD IPv6 stack in that we implemented special restrictions (at that time) on anycast addresses and had experimentally assigned subnet-router anycast addresses on PC-based IPv6 routers. In general, it's difficult to declare something hasn't been implemented because it eliminates any minor implementation activity, which is almost impossible to prove. I have no objection to the conclusion itself (i.e. not a problem in practice) and would rephrase it to something like this: However, Subnet-router anycast addresses have not been (widely) deployed, and this has not been a problem in practice. 2. In section 5, it states: 1) A rule described in ICMPv6 [RFC4443] indicates that a Destination Unreachable (Code 3) message should be sent by a router rather than forwarding packets back onto point-to-point links from which they were received if their destination address belongs to the link itself. This sentence is clear, but IMO is not perfectly accurate because an address doesn't belong t(or isn't assigned to) a *link*; it's assigned to an interface. The corresponding text of RFC4443 reads: One specific case in which a Destination Unreachable message is sent with a code 3 is in response to a packet received by a router from a point-to-point link, destined to an address within a subnet assigned to that same link (other than one of the receiving router's own addresses). where it's a *subnet* that is assigned to the link. So, to be very accurate, I'd propose to revise the text (e.g.) as follows: 1) A rule described in ICMPv6 [RFC4443] indicates [...] if their destination address matches a subnet that belongs to the link itself. --- JINMEI, Tatuya Internet Systems Consortium, Inc. -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------