Re: draft-shirasaki-dualstack-service-02.txt CPE assigned Host Address Lifetime issue

[SHIRASAKI Yasuhiro <yasuhiro@nttv6.jp>]

On Mon, 16 Feb 2004 14:15:36 +0900,
JINMEI Tatuya / 神明達哉 <jinmei@isl.rdc.toshiba.co.jp> wrote:
> >>>>> On Mon, 16 Feb 2004 13:35:21 +0900 (JST), 
> >>>>> SHIRASAKI Yasuhiro <yasuhiro@nttv6.jp> said:
> 
> >> If so, I'd say the host is not fully compliant (at least not compliant
> >> to RFC3484), and network operators should not assume such a behavior.
> 
> > Exactly.
> 
> > I got your point, but if so, in the situation where delegated prefix is
> > volatile (like PD with prefix-pool, as Green mentioned), how CPE should do?
> 
> > - CPE sets preferred lifetime in RA with very small value (ex. 1 min)
> >   and advertises with a short period (20sec?).
> > - CPE has a stable storage and advertises an old prefix with pltime
> >   = 0, when CPE reboots accidentally and a delegated prefix is changed.
> 
> For the reboot case, perhaps a desirable behavior is:
> 
> - detect the old prefix is now invalid (as described in Section 12.1
>   of RFC3633)
>   
> - advertise the old prefix with zero lifetimes for a while.  The zero
>   preferred lifetime will deprecate the old address immediately.  The
>   zero valid lifetime will at least reduce the corresponding valid
>   lifetime to two hours, and the old address will be removed in two
>   hours.

Agreed. so that, CPE must have a stable storage to store the old prefix.

--
SHIRASAKI Yasuhiro @ NTT Communications
t: +81-3-6800-3262, f: +81-3-5365-2990