Re: [apps-discuss] Apps Area Review of draft-ietf-behave-lsn-requirements-05

[Eliot Lear <[e-mail]>]

Hi Simon,

Just to be clear, I'm not asking you to specifically support any
protocol, but to explain your logic as to what your requirements are. 
If you and the working group decide that it is not practical for one
reason or another to support DCCP (or any other protocol) that's fine. 
Just expose your logic.

Eliot

On 12/15/11 6:57 PM, Simon Perreault wrote:
> On 2011-12-15 02:04, Eliot Lear wrote:
>>> I'm sorry, I don't know how to translate that into text. RFC6269
>>> appears clear
>>> to me. Do you have an example of text you would like to see?
>>
>> Don't end with this, but you can start with this.  Because
>> subscribers do not
>> receive unique IP addresses, Carrier Grade NATs introduce substantial
>> limitations
>> in communications between subscriber that were not previously there
>> .  In
>> particular, it is considerably more involved to establish proxy
>> functionality at
>> the subscriber border.  Some applications may require substantial
>> enhancements,
>> while some may not function at all in such an environment.  Please
>> see RFC 6269
>> for details.
>
> Tweaked a bit, gives this:
>
>      <t>Because subscribers do not receive unique IP addresses,
> Carrier Grade
>        NATs introduce substantial limitations in communications between
>        subscribers and with the rest of the Internet. In particular,
> it is
>        considerably more involved to establish proxy functionality at
> the border
>        between internal and external realms.  Some applications may
> require
>        substantial enhancements, while some others may not function at
> all in
>        such an environment.  Please see <xref target="RFC6269"/> for
>        details.</t>
>
>>>>   * Req1: Whither SCTP?  At the very least someone should say
>>>> something about why
>>>>     SCTP is NOT on the list.
>>>
>>> There are BEHAVE RFCs we can cite regarding NAT behaviour for TCP,
>>> UDP, and
>>> ICMP. There is none for SCTP. If there was one we could debate this.
>>> But right
>>> now it's just impossible to say "support SCTP" without saying how
>>> this is done.
>>
>> Dave addressed this.  What about DCCP and RFC 5596?  My main point is
>> that you
>> explain your logic as you did above.  And...
>
> You're right, there is an RFC specifying NAT behaviour for DCCP: RFC5597.
>
> On the one hand, as a probable future CGN captive, I'm tempted to say
> "all CGNs MUST support RFC5597!"
>
> On the other, I know it would probably be a frivolous requirement that
> won't get implemented.
>
> *sigh*
>
> Then there is also this: draft-ietf-dccp-udpencap-09
>
> Here's a proposal: add a sub-requirement saying something like "If a
> CGN forwards DCCP packets, then it MUST support [RFC5597]."
>
> Simon