On Sun, 6 Mar 2011 09:54:42 +0100 (CET) Mikael Abrahamsson <[email protected]> wrote:
> On Sun, 6 Mar 2011, Mark Smith wrote: > > > I don't think that will always work. The PIO is needed to indicate to > > end-nodes what the onlink prefix(es) are, as per RFC5942. > > Why do they need to know that? > > In our testing at least under Linux did just fine by knowing how to reach > the router and that it needed to use (and actually used) DHCPv6 to get its > IPv6 address. No on-link prefix was needed (or even desireable in some > deployment scenarios). > The PIO isn't to make DHCPv6 work, it is to inform the end-host of what destinations are onlink. Here is what RFC5942 says - The behavior of IPv6 as specified in Neighbor Discovery (ND) [RFC4861] is quite different. The on-link determination is separate from the address assignment. A host can have IPv6 addresses without Singh, et al. Standards Track [Page 2] ^L RFC 5942 IPv6 Subnet Model July 2010 any related on-link prefixes or can have on-link prefixes that are not related to any IPv6 addresses that are assigned to the host. Any assigned address on an interface should initially be considered as having no internal structure as shown in [RFC4291]. In IPv6, by default, a host treats only the link-local prefix as on-link. The reception of a Prefix Information Option (PIO) with the L-bit set [RFC4861] and a non-zero valid lifetime creates (or updates) an entry in the Prefix List. All prefixes on a host's Prefix List (i.e., those prefixes that have not yet timed out) are considered to be on-link by that host. > Does RFC5942 says this is mandatory? It updates 4861. > I interpret 4.1 as this is definitely > not mandatory, rather the opposite? > I'm not quite sure which 4.1 you're referring to. Point 1. of section 4 of RFC5942? -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
