Re: [pcp] PREFIX64 PCP Option for NAT64: draft-boucadair-pcp-nat64-prefix64-option

[Simon Perreault <[e-mail]>]

Mohamed,

Thanks for the very detailed answer! The background story is much 
clearer to me now.

Le 2012-09-06 09:20, [e-mail] a écrit :
>> Consider a PCP client that receives a MAP response containing a
>> PREFIX64 option. Does the option apply a) only to the mapping
>> contained in the MAP response, or b) to all future mappings as
>> well?
>
> Med: I'm tempted to say the prefix will be used for all mappings
> associated with the same PCP server. A record to associate a PCP
> server and a PREFIX64 should be maintained by the client. We need to
> check if there are scenarios where the same PCP Server controls
> NAT64s configured with distinct PREFIX64 servicing the same IPv6-only
> host.

I still have a problem with this. The problem is that the PREFIX64 data 
should not be associated with a MAP request because it is global to the 
server. Returning it as part of a MAP response makes no sense to me.

Suggestion: why not create a new opcode for querying server-global 
parameters? The PCP client would use this opcode once, get the PREFIX64 
data in the response, then would do MAP requests separately as usual. I 
think this would result in clearer semantics and implementations.

Simon
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