Re: [pcp] PCP Server Selection - Address Family Selection

[Dan Wing <[e-mail]>]

On Apr 25, 2014, at 7:57 AM, Simon Perreault <[e-mail]> wrote:

> Le 2014-04-25 10:51, Sebastian Kiesel a écrit :
>> draft-ietf-pcp-server-selection-02  says in Section 3:
>> 
>>   1.  If the PCP client can use both address families when
>>       communicating to a particular PCP server, the PCP client SHOULD
>>       select the source address of the PCP request to be of the same IP
>>       address family as its requested PCP mapping (i.e., the address
>>       family of the Requested External IP Address).
>> 
>> 
>> What is the reason for saying it SHOULD use the same familiy as the
>> requested EXTERNAL IP address?  I think it would make more sense to use
>> the same familiy as the INTERNAL address (if there is a difference at
>> all).
> 
> +1
> 
> I stated this in my review.

The intent of the wording is to avoid NAT64 (or NAT46) where NAT44 or no NAT was necessary at all.  If the wording is backwards, let's fix it.  I have now read it three times, and the existing text seems to avoid NAT64.  In any event, yes, there should be an explanation ("To avoid unnecessary IP address family translation, ...").

-d