Re: [netext] Chair review of I-D: draft-ietf-netext-pd-pmip (05)

[Peter McCann <[e-mail]>]

Basavaraj Patil wrote:
>
> 5. How does the MAG know that it needs to allow forwarding of packets 
> via the PMIP6 tunnel for packets with SRC address that are derived 
> from the delegated prefixes? Its not clear if there is added 
> functionality needed at the MAG to accomplish this.

I think there are potentially some deeper issues here.

The MN sees the original MAG as its "delegating router".  When the
MN changes to a new MAG, there is no good way to tell that the
delegated prefixes are still routable to the link.  The delegating
router has become unreachable.  The new router may send an RA that
advertises the original link prefix, and so the MN can tell that
its SLAAC unicast addresses are still valid on the link.  However,
RFC 3633 says that the delegated prefix is NOT advertised on the
link between the delegating router and the requesting router.
Therefore, there is no way for the MR to determine whether it can
still use the delegated prefixes, other than perhaps re-running
DHCPv6-PD on the new link.

-Pete