On 02/08/2013 18:12, Mark ZZZ Smith wrote:
>
> ----- Original Message -----
>> From: Mark ZZZ Smith <[email protected]>
>> To: C. M. Heard <[email protected]>; IPv6 <[email protected]>
>> Cc:
>> Sent: Friday, 2 August 2013 2:55 PM
>> Subject: Re: UDP+Fragmentation (was: "Deprecate")
>>
>> Hi,
>>
>>
>> ----- Original Message -----
>>> From: C. M. Heard <[email protected]>
>>> To: IPv6 <[email protected]>
>>> Cc:
>>> Sent: Friday, 2 August 2013 3:11 AM
>>> Subject: Re: UDP+Fragmentation (was: "Deprecate")
>>>
> <snip>
>>> - generic transport encapsulation within UDP (suggested to me
>>> off-list by Mark Smith, based on a draft by Stuart Cheshire
>>> et. al.).
>>>
>> For those on the list, the draft I mentioned was :
>>
>> Encapsulation of TCP and other Transport Protocols over UDP
>> http://tools.ietf.org/html/draft-cheshire-tcp-over-udp-00
>>
>>
>> Note that this basically proposes translating the TCP header into UDP header
>> fields, and then for the missing fields, appending them after the UDP
>> header. I
>> was a bit confused by what was proposed, until I thought about a web server
>> specifically listening on UDP port 80, knowing that UDP port 80 is TCP over
>> UDP,
>> and then decoding the UDP fields and subsequent fields as a TCP header.
>>
> And actually to better clarify, my (quick) suggestion was to put
> fragmentation fields after the UDP header, similar to how that draft places
> the TCP fields after the UDP header.
May I make a plea for any such proposal to be carefully evaluated against
common practices in stateful firewalls and load balancers. I'm rather concerned
that the problems these middleboxes create with conventional fragmentation
will soon come back with UDP-encapsulated fragmentation. (There is no problem
in computer science that can't be made harder by recursion.)
Brian
--------------------------------------------------------------------
IETF IPv6 working group mailing list
[email protected]
Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------
