Re: [Softwires] 4rd Address Mapping - version-01

[Jacni Qin <[e-mail]>]

Hi,

On 9/29/2011 2:00 PM, Ole Troan wrote:
> Jacni,
>
>>> I would be tempted to suggest that we write a "an implementation MUST NOT make this assumption" in the MAP draft.
>>> and that we in IETF documents write this as if there is a prefix reserved for address mapping.
>>> in the general case there is no way to guarantee that a host doesn't pick the same IID. and we'll have to specify how this would work with DAD and proxy ND. I'd rather not. left up to the implementor is my suggestion...
>> Taking the EUI-64 into account, a careful design of the 4rd IID can make the probability of conflicts quite low. Then as you mentioned, DAD would further reduce it.
>> Anyway, that's not to say I'm in favor of this design, the reason I see, of doing this is just to accommodate the double translation while not affect at all the IPv6 addressing (a reserved prefix? no ...).
> the DAD/ND redirect solution would fail in the routed home case. i.e. the case where there is multiple levels of routers in the network.
ok, I get your case.


Cheers,
Jacni

> that's why I think the recommendation should be to use one /64 of the delegated prefix to the translation "pool".
>
> cheers,
> Ole