Re: [Softwires] Proposed Unified Address Mapping for encapsulation and double-translation

[GangChen <[e-mail]>]

Hello Remi,

Thanks for the answers.
Please see my reply inline.

2011/10/5, Rémi Després <[e-mail]>:
>> There are no necessary to put IPv4 and Port-set ID information in last
>> 64 bits.
>
> The CE Pv6 prefix included in the /64 Subnet prefix isn't self delimited, so
> that the length of the CE index can't be determined in this part of the
> address.
> Having the length of the A or A+P prefix in the IID completes what is needed
> to derive the CE port-set.

I understand such encoded information helps deriving a shared IPv4
address. However, I guess it's not necessary to dig up such
information if we only take traffic contronl on IPv6 data plane (as I
said below)


>> It may help encapsulation in same cases(e.g. IPv4 based traffic
>> classification,IPv4 ACL, etc).
>> However, the translation case is more preferable doing pure IPv6 based
>> control for the sake of simpler operation reasons (e.g. IPv6 ACL).
>> It's desirable identifying a customer depending on first 64 bits.
>
> A point is that, although some realistic deployments may ignore what is made
> available in IIDs (at least at the beginning), some others would take
> advantage of it.

Yes. I agree with your point here. As you said such IID design may not
be taken effect on some realistic deployments, I would like to suggest
the IID MAY not appeared in double translation cases.


Many thanks

Gang