RE: WG Last Call: draft-ietf-v6ops-mech-v2-01.txt

[Pekka Savola <pekkas@netcore.fi>]

On Thu, 6 Nov 2003, Randy Bush wrote:
> > Note that there have been a large number of updates since the original
> > transmech.
> 
> perhaps a small enumeration of the technical changes of substance
> would help us decide if this needs to recycle at ps.

These are available in the draft, in "Changes from RFC 2893" section.  

I think the most major ones, in addition to removing automatic tunneling,
have been the changes in the MTU parts of the spec.  I believe that
ingress-filtering has also changed.  I don't think many (or close to any)  
implementations conform to the spec out of the box, which is why I was 
edging towards PS myself.  But I'd be happy to be convinced otherwise!

I'll copy it below (minus the ones that seem mostly only editorial):

   -    Removed automatic tunneling and use of IPv4-compatible
        addresses.

   -    Removed default Configured Tunnel using IPv4 "Anycast Address"

   -    Dropped "or equal" in if (IPv4 path MTU - 20) is less than or
        equal to 1280

   -    Clarified that the dynamic path MTU mechanism in section 3.2 is
        OPTIONAL but if it is implemented it should follow the rules in
        section 3.2.

   -    Stated that when the dynamic PMTU is not implemented the sender
        MUST NOT by default send IPv6 packets larger than 1280 into the
        tunnel.

   -    Stated that implementations MAY have a knob by which the MTU can
        be set to larger values on a tunnel by tunnel basis, but that
        the default MUST be 1280 and that decapsulators need to be
        configured to match the encapsulator's MTU.

   -    Clarified text about ingress filtering e.g. that it applies to
        packet delivered to transport protocols on the decapsulator as
        well as packets being forwarded by the decapsulator, and how the
        decapsulator's checks help when IPv4 and IPv6 ingress filtering
        is in place.


-- 
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings