Thx Brian, will do.


On Oct 27, 2010, at 6:41 PM, "Brian E Carpenter" <[email protected] 
 > wrote:

> You can refer to RFC 2983 "Differentiated Services and Tunnels."
> (Informational RFC)
>
> Regards
>   Brian Carpenter
>
> On 2010-10-28 05:32, Lee, Yiu wrote:
>> Agreed. Thx.
>>
>> From: Jacni Qin <[email protected]<mailto:[email protected]>>
>> Date: Thu, 28 Oct 2010 00:19:42 +0800
>> To: Brian E Carpenter 
>> <[email protected]<mailto:[email protected] 
>> >>
>> Cc: Softwires <[email protected]<mailto:[email protected]>>
>> Subject: Re: [Softwires] I-D Action:draft-lee-softwire-dslite- 
>> deployment-00.txt
>>
>> One more comment on Section 2.8,
>>
>> "...It is recommended the AFTR to copy the DSCP value in the IPv4  
>> header to the IPv6 header after the encapsulation."
>>
>> I guess a similar function is needed on B4 for the upstream  
>> traffic. Add it somewhere in the B4 section? :-)
>>
>>
>> Cheers,
>> Jacni
>>
>>
>>
>> On Wed, Oct 27, 2010 at 10:13 AM, Brian E Carpenter 
>> <[email protected] 
>> <mailto:[email protected]>> wrote:
>> Hi,
>>
>>> 2.  AFTR Deployment Considerations
>> ...
>>>   IPv4.  Although an operator can configure a dual-stack interface  
>>> for
>>>   both functions, we strongly recommended to configure two  
>>> individual
>>>   interfaces (i.e. one dedicated for IPv4 and one dedicated for  
>>> IPv6)
>>>   to segregate the functions.
>>
>> Can you clarify whether this means two physical interfaces or
>> two logical software interfaces?
>>
>>> 2.1.  MTU Considerations
>> ...
>>>   For fragmentation problem shares among all the tunneling  
>>> protocols,
>>>   this is not unique to DS-Lite.  The IPv4 packet isn't over- 
>>> sized, it
>>>   is the v6 encapsulation that MAY cause the oversized issue.
>>
>> I must confess I am a bit confused. The IPv6 minimum MTU is so much  
>> larger
>> than 576 that I don't see how you can fail to support the IPv4  
>> minimum
>> MTU.
>>
>> OK, suspending my disbelief on that point:
>>
>>>                                                                So  
>>> the
>>>   tunnel points are responsible to handle the fragmentation.  In
>>>   general, the Tunnel-Entry Point and Tunnel-Exist Point should
>>>   fragment and reassemble the oversize datagram.
>>
>> I understand that, if DF is not set, the tunnel entry point (or more
>> accurately, the IPv4 entity forwarding the packet into the tunnel
>> entry point) should fragment the packet. But unless you are re- 
>> inventing
>> SEAL, the tunnel exit point will just forward the fragments, won't  
>> it?
>>
>>> 2.2.  Lawful Intercept Considerations
>>
>> Given RFC 2804, I suggest deleting this section.
>>
>>> 2.3.  Logging at the AFTR
>>
>> The arguments in this section are pretty powerful, but I wonder
>> whether they belong in v6ops, rather than in a more general analysis
>> of CGN/LSN/NAT444 issues such as draft-ietf-intarea-shared- 
>> addressing-issues.
>>
>>> 2.6.  Strategic Placement of AFTR
>> ...
>>>   The AFTR architecture design, then, is mostly figuring out the
>>>   strategic placement of each AFTR to best use the capacity of each
>>>   public IPv4 address without oversubscribing the address or  
>>> overtaxing
>>>   the AFTR itself.  Although only a few studies of per-user port  
>>> usage
>>>   have been done, an AFTR should be able to support 3000 - 5000  
>>> users
>>>   per public IPv4 address.
>>
>> I find this number astonishing. We know that 200 open ports per  
>> user has
>> been reported as typical in some ISP secnarios; that suggests that  
>> even as
>> many as 300 users per public adress is close to the limit.
>>
>> Regards
>>  Brian Carpenter
>> _______________________________________________
>> Softwires mailing list
>> [email protected]<mailto:[email protected]>
>> https://www.ietf.org/mailman/listinfo/softwires
>>
>> _______________________________________________ Softwires mailing  
>> list [email protected]<mailto:[email protected]> 
>> https://www.ietf.org/mailman/listinfo/softwires
>>
_______________________________________________
Softwires mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/softwires

Reply via email to