Re: [Softwires] MAP and 4rd - Relationship with Single translation

[Xing Li <[e-mail]>]

Hi, Remi,

于 2012/3/9 21:39, Rémi Després 写道:
> Hi Xing,
>
> Le 2012-03-09 à 08:17, Xing Li a écrit :
>
>> Hi, Remi,
>>
>> 于 2012/2/10 18:23, Rémi Després 写道:
>>> Hi Xing,
>>> Good to have you coming in the (unfinished) technical analysis.
>>>
>>> I answered to Ole on his remarks, which you support, but not on 
>>> the following:
>>>
>>> You propose to have a line on "IPv4 to IPv6 communication (single 
>>> translation) supported", wit
>
>>> Let me therefore reiterate the wish to see an ISP use case, with its 
>>> Mapping rules, and with IPv6 prefixes of CEs that illustrate the 
>>> problem you see.
>>
>> The CERNET2 is an IPv6-only core network. We provide stateless 
>> IPv4/IPv6 translation between CERNET2 and the IPv4 core network 
>> (CERNET). The users can either use single translation directly, or 
>> add their own IPv4/IPv6 translor if double translation is required.
>>
>> Is this answer your question?
>
> Not quite, since neither example MAP-T Mapping rules nor assigned IPv6 
> prefixes are provided, but that may be sufficient so far.
>
>  A key point is that 4rd doesn't prevent a 4rd-capable dual-stack CE 
> node, when it receives no 4rd mapping rule, to exercise single 
> translation.
>  Actually, I believe that using for this the BIH of RFC6535 is both 
> sufficient and recommendable.
>  Translated IPv4 packets, because they are sent from CE nodes to DNS64 
> synthesized addresses, are appropriately routed to their destinations. 
> (It can be via the NAT64-CGN if needed, or via more direct paths if 
> possible.)
> Anything missed?

Sorry, this is a misunderstanding.
Hint: Single translation and double translation are based on the same 
mapping rule in the CERNET2 deployment.

Regards,

xing


>
> Regards,
> RD
>
>
>
>
>
>> Regards,
>>
>> xing
>>
>>
>>>
>>> Regards,
>>> RD
>>>
>>>
>>>
>>>
>>> Le 2012-02-10 à 04:28, Xing Li a écrit :
>>> ...| | | | |
>>>>>>    |  5 | IPv6 web caches work for IPv4        |  Y  |  N  |  Y  |  N  |
>>>>>>    |    | packets                              |     |     |     |     |
>>>>> suggest you rename to "IPv4 to IPv6 communication (single translation) supported"
>>>>>
>>>>
>>>> (2) More clarification should be added here. I am not sure 4rd-H 
>>>> can support single translation.
>>>>
>>>> (a) According to (1), 4rd-H does not perform header translation 
>>>> defined by RFC6145.
>>>>
>>>> (b) In the softwire mailing list, it seems that 4rd-H cannot 
>>>> support single translation.  See the thread containing 
>>>> http://www.ietf.org/mail-archive/web/softwires/current/msg03324.html and 
>>>> other posts.
>>>>
>>>> (c) If 4rd-H cannot support single translation, then "IPv6 web 
>>>> caches work for IPv4 packets" requires special configurations, it 
>>>> cannot do IPv6 web caches for non 4rd-H packets.
>>>
>>> ...
>>>
>>>> (5) I would like to see the details of how 4rd-H handles ICMP and 
>>>> ICMP error messages. In the softwire mailing list there were some 
>>>> discussions. See the thread containing 
>>>> http://www.ietf.org/mail-archive/web/softwires/current/msg03324.html and 
>>>> other posts.Please add
>>>>
>>>> | 17 | Handle ICMP (RFC6145) | Y | n/a | ? | ? |
>>> ...
>>>
>>
>