Hi Thomas, On 4/27/11 8:34 AM, Thomas Narten wrote: > Brian Haberman <br...@innovationslab.net> writes: > >> That draft has been replaced with draft-ietf-6man-rpl-routing-header. I >> suggest that you take a look at that draft (currently being reviewed by >> the IESG), especially section 4. > > Hmm. Section 4 says: > >> Routers SHOULD >> use IPv6-in-IPv6 tunneling, as specified in [RFC2473] to include a >> new SRH in datagrams that are sourced by other nodes. > > SHOULD would be OK, here, if there was some alternative that might be > appropriate on some situations. But the document is silent on those > alternatives. In which case, I wonder why this is not a MUST. Is it > because other types of tunneling would be OK? (If so, giving such an > example would be good).
I would assume that any type of tunneling would be allowed (e.g., GRE), and agree that it would be useful to enumerate at least general situations where the SHOULD can be ignored. I *thought* some of those alternatives were discussed in the RPL spec, but they don't appear to be (draft-ietf-roll-rpl). > > But then later: > > In very specific cases, IPv6-in-IPv6 tunneling may be undesirable due > to the added cost and complexity required to process and carry a > datagram with two IPv6 headers. [I-D.hui-6man-rpl-headers] describes > how to avoid using IPv6-in-IPv6 tunneling in such specific cases and > the risks involved. > > I strongly object to this text. It suggests that that other > approaches, presumably including those that violate existing IETF > specs, might be OK too. We should not do this. > > Or am I missing something here? I perused draft-hui-6man-rpl-headers and it appears to describe how to insert/remove the RPL routing header at the RPL network border. Would you prefer if the exception alluded to above via reference to that draft be explicitly included in this draft? Regards, Brian -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
