[SIPForum-discussion] Need help about RFC 3262
Jun KOSHIKO
j.koshiko at east.ntt.co.jp
Wed Jul 11 09:01:39 UTC 2007
Inline.
> Hi
>
> I know what 'reliable response' means,
> I only want to know that,
> the 'reliable responses' there(in 3262),
> have SDP or not.
>
> For example, the UAS have sent a reliable 183(with SDP),
> but not received PRACK yet, at that time,
> if it wanted to send 200(INVITE), it's OK ?
Not OK. Offer/answer negotiation won't work.
> If 183 had not SDP, it's OK ?
OK.
As you referred, RFC3262 allows UAS to send a final response even if
it hasn't received PRACK for reliable 18x, but there is an exception
that it is prohibited to send 200OK if any of reliable 18xs include SDP.
RFC3262 page5
The UAS MAY send a final response to the initial request before
having received PRACKs for all unacknowledged reliable provisional
responses, unless the final response is 2xx and any of the
unacknowledged reliable provisional responses contained a session
description. In that case, it MUST NOT send a final response until
those provisional responses are acknowledged. If the UAS does send a
final response when reliable responses are still unacknowledged, it
SHOULD NOT continue to retransmit the unacknowledged reliable
provisional responses, but it MUST be prepared to process PRACK
requests for those outstanding responses. A UAS MUST NOT send new
reliable provisional responses (as opposed to retransmissions of
unacknowledged ones) after sending a final response to a request.
> Date: Wed, 11 Jul 2007 16:46:28 +0900From: j.koshiko at east.ntt.co.jpTo: ggmylove at hotmail.comSubject: Re: [SIPForum-discussion] Need help about RFC 3262CC: discussion at sipforum.org
>
> "Reliable response" means a response which include Require header with 100rel.
> UAS can put "Require: 100rel" to provisional responses in order to ask UAC
> to send PRACK for the provisional response.
>
> Session description is independent of whether a response is reliable or not.
> Reliable responses may or may not include SDP.
>
> Hope this help.
>
> > Hi,All
> >
> > At the end of '3 UAS Behavior' RFC 3262,
> >
> > The UAS MAY send a final response to the initial request before
> > having received PRACKs for all unacknowledged reliable provisional
> > responses, unless the final response is 2xx and any of the
> > unacknowledged reliable provisional responses contained a session
> > description. In that case, it MUST NOT send a final response until
> > those provisional responses are acknowledged. If the UAS does send a
> > final response when reliable responses are still unacknowledged, it
> > SHOULD NOT continue to retransmit the unacknowledged reliable
> > provisional responses, but it MUST be prepared to process PRACK
> > requests for those outstanding responses.
> >
> > Can some one tell me, the red words 'reliable responses ' mean 'provisional responses contained a session description' or 'provisional responses without a session description'.
> >
> > thanks & regards,
> > Minglu
> _________________________________________________________________
> ハケモテマツメサエ〓ト MSN Messenger。」
> http://imagine-msn.com/messenger/launch80/default.aspx?locale=zh-cn&source=wlmailtagline
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20070711/0b7e69df/attachment-0002.html>
More information about the discussion
mailing list