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<font face="monospace">Hi,<br>
<br>
See <a class="moz-txt-link-freetext" href="https://www.ietf.org/rfc/rfc3261.html#section-16.7">https://www.ietf.org/rfc/rfc3261.html#section-16.7</a>, top page
110<br>
<br>
</font><br>
<pre class="newpage"> After a final response has been sent on the server transaction,
the following responses MUST be forwarded immediately:
- Any 2xx response to an INVITE request
Regards,
</pre>
<font face="monospace"></font>
<pre class="moz-signature" cols="72">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a class="moz-txt-link-freetext" href="https://www.opensips-solutions.com">https://www.opensips-solutions.com</a>
<a class="moz-txt-link-freetext" href="https://www.siphub.com">https://www.siphub.com</a></pre>
<div class="moz-cite-prefix">On 6/29/23 4:21 PM, Alexander Kogan
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:e4c8e27c-f00d-9c49-870b-fc717f91cb48@5gfuture.com">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<p>Ohh... I've looked through 3261 again, and haven't found the
case.... Could you please point me?</p>
<p>The RFC says a proxy makes a separate client transaction for
each outgoing branch. Each client transaction is finished with
the first final response received (or generated internally
according to 8.1.3.1 Transaction Layer Errors - "When a timeout
error is received from the transaction layer, it MUST be treated
as if a 408 (Request Timeout) status code has been received")
and any other final responses for this transaction are out of
state, isn't it?<br>
</p>
<pre class="moz-signature" cols="72">Best regards,
Alexander Kogan,
Director of R&D
5g Future
<a class="moz-txt-link-freetext" href="http://5gfuture.com" moz-do-not-send="true">http://5gfuture.com</a>
</pre>
<div class="moz-cite-prefix">On 29.06.2023 16:05, Bogdan-Andrei
Iancu wrote:<br>
</div>
<blockquote type="cite"
cite="mid:48a8d102-15be-06a8-808c-fd3c08ba3747@opensips.org">
<meta http-equiv="Content-Type" content="text/html;
charset=UTF-8">
<font face="monospace">YEs, 200 OK is accepted on top of any
previous negative reply...that's the RFC :)<br>
<br>
Regards,<br>
</font>
<pre class="moz-signature" cols="72">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a class="moz-txt-link-freetext" href="https://www.opensips-solutions.com" moz-do-not-send="true">https://www.opensips-solutions.com</a>
<a class="moz-txt-link-freetext" href="https://www.siphub.com" moz-do-not-send="true">https://www.siphub.com</a></pre>
<div class="moz-cite-prefix">On 6/28/23 4:38 PM, Alexander Kogan
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:3306381c-677a-fa07-b911-1e080498cb0c@5gfuture.com">
<meta http-equiv="Content-Type" content="text/html;
charset=UTF-8">
<p>BTW, we have the line in log when 200 has been received for
timed out branch:</p>
<p>/usr/sbin/opensips[9653]: DBG:tm:reply_received: org.
status uas=180, <font color="#ff0000"><b>uac[1]=408</b></font>
local=0 is_invite=1)</p>
<p>Of course, it's a fake reply generated on timeout. Does it
mean that if OpenSIPS receives a real final reply >=300
and after that it will receive 200, it will pass 200 to the
caller?<br>
</p>
<pre class="moz-signature" cols="72">Best regards,
Alexander Kogan,
Director of R&D
5g Future
<a class="moz-txt-link-freetext" href="http://5gfuture.com" moz-do-not-send="true">http://5gfuture.com</a>
</pre>
<div class="moz-cite-prefix">On 28.06.2023 15:01, Alexander
Kogan wrote:<br>
</div>
<blockquote type="cite"
cite="mid:0014a55b-dd98-d6a3-d61c-38dced0308e0@5gfuture.com">Well,
it would have worked if I didn't need loops.... <br>
<br>
Best regards, <br>
Alexander Kogan, <br>
Director of R&D <br>
5g Future <br>
<a class="moz-txt-link-freetext" href="http://5gfuture.com"
moz-do-not-send="true">http://5gfuture.com</a> <br>
<br>
<br>
On 28.06.2023 14:06, Bogdan-Andrei Iancu wrote: <br>
<blockquote type="cite">True, multiple 200 OK replies will
mess up the dialog module, as the module is not able to
separately keep track of the calls deriving from the same
original dialog... <br>
You may have good chances to get it work almost correctly
if using the sip only dialog matching (in dialog module),
as the to-tag will make the difference between the two
calls resulted from the original dialog. <br>
<br>
Regards, <br>
<br>
Bogdan-Andrei Iancu <br>
<br>
OpenSIPS Founder and Developer <br>
<a class="moz-txt-link-freetext"
href="https://www.opensips-solutions.com"
moz-do-not-send="true">https://www.opensips-solutions.com</a>
<br>
<a class="moz-txt-link-freetext"
href="https://www.siphub.com" moz-do-not-send="true">https://www.siphub.com</a>
<br>
<br>
On 6/28/23 11:05 AM, Alexander Kogan wrote: <br>
<blockquote type="cite">Agreed, it's really ugly. But on
practice it means that the caller has two confirmed
dialogs with the same did, but opensips has only one.
And when caller sends BYE for one of its dialogs it
ruins the dialog on OpenSIPS.... So it seems much better
to make an ugly solution... <br>
<br>
Best regards, <br>
Alexander Kogan, <br>
Director of R&D <br>
5g Future <br>
<a class="moz-txt-link-freetext"
href="http://5gfuture.com" moz-do-not-send="true">http://5gfuture.com</a>
<br>
<br>
<br>
On 28.06.2023 11:52, Bogdan-Andrei Iancu wrote: <br>
<blockquote type="cite">Hi Alexander. <br>
<br>
The problem here is not related to the ability or
inability of OpenSIPS to drop the late 200 OK - the
problem is you MUST not drop it, as you will break the
signaling. Again, a callee party sending a 200 OK
expects an ACK and nothing else. <br>
If you drop (on OpenSIPS level) the late 200 OK, the
vendor 1 will remain inconsistent - it will keep
retransmitting the 200 OK as it expected the ACK for
it. <br>
<br>
Of course, there is the ugly approach of "playing
dead", dropping every single late 200 OK from Vendor
1, forcing it to generate a BYE (eventually) and close
the call. But this is something really ugly. <br>
<br>
Regards, <br>
<br>
Bogdan-Andrei Iancu <br>
<br>
OpenSIPS Founder and Developer <br>
<a class="moz-txt-link-freetext"
href="https://www.opensips-solutions.com"
moz-do-not-send="true">https://www.opensips-solutions.com</a>
<br>
<a class="moz-txt-link-freetext"
href="https://www.siphub.com" moz-do-not-send="true">https://www.siphub.com</a>
<br>
<br>
On 6/28/23 10:13 AM, Alexander Kogan wrote: <br>
<blockquote type="cite">Hi, <br>
<br>
I got the point. Nevertheless, isn't it a good idea
to have a way to discard messages of branches that
have already been timed out instead of reanimating
them? E.g. t_check() could return -2 in
reply_received(), or drop() action could be allowed
for 200... <br>
<br>
Best regards, <br>
Alexander Kogan, <br>
Director of R&D <br>
5g Future <br>
<a class="moz-txt-link-freetext"
href="http://5gfuture.com" moz-do-not-send="true">http://5gfuture.com</a>
<br>
<br>
<br>
On 28.06.2023 10:37, Bogdan-Andrei Iancu wrote: <br>
<blockquote type="cite">Hi Alexander, <br>
<br>
According to RFC3261, there is noting a proxy
should/must do about a received 200 OK rather than
sending further to the caller (even if the 200 OK
is received on an old branch). Basically, if for
whatever reasons you end up getting 200 OK from
several branches of the same transaction, you need
to forward them all to caller - why? as in SIP,
once a 200 OK was fired by a callee device, there
is no signaling /mechanism available to
"cancel"/"reject"/"discard" that it. The only way
to handle "unwanted" 200 OK is to accept it, ack
it and then send a BYE for it. <br>
Now, as a proxy does not have the necessary
"logic" to decide which 200 OK to keep and which
to BYE, there is nothing to be done than "moving"
this decision to the caller - so pass all the 200
OK to caller and let it decide which to keep or
not. <br>
<br>
Regards, <br>
<br>
Bogdan-Andrei Iancu <br>
<br>
OpenSIPS Founder and Developer <br>
<a class="moz-txt-link-freetext"
href="https://www.opensips-solutions.com"
moz-do-not-send="true">https://www.opensips-solutions.com</a>
<br>
<a class="moz-txt-link-freetext"
href="https://www.siphub.com"
moz-do-not-send="true">https://www.siphub.com</a>
<br>
<br>
On 6/27/23 5:59 PM, Alexander Kogan wrote: <br>
<blockquote type="cite">Hello, <br>
<br>
I've got such a call flow: <br>
<br>
Client OpenSIPS <br>
|--INVITE-->| <br>
|<--100-----| Vendor1 <br>
| |--INVITE-->| <br>
| |--INVITE-->| <br>
| |--INVITE-->| <br>
| | | Vendor2 <br>
| |--INVITE------------- >| <br>
| |<--100-----------------| <br>
| |<--180-----------------| <br>
|<--180-----| | <br>
| |<--200-----------------| <br>
|<--200-----| | <br>
| | | <br>
| |<--200-----| | <br>
|<--200-----| | <br>
| | | | <br>
<br>
The first branch was timed out and we switched
up to the next one. A bit later we received 200
OK from the first one. The question is - how to
avoid passing 200 to the first leg? drop()
doesn't work for final responses. I also can't
use t_cancel_branches() because it works in
onreply_route only which is not called in case
of timeout.... <br>
<br>
</blockquote>
<br>
</blockquote>
</blockquote>
<br>
</blockquote>
</blockquote>
<br>
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