<div dir="ltr"><div>Hi Alex,</div><div><br></div><div>Thank you for that. Do you offhand know of an easy way to test if the sendonly attribute is set? Presumably we can use sdp_remove_line_by_prefix() to remove it.,</div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, 9 Dec 2020 at 20:52, Alex Balashov <<a href="mailto:abalashov@evaristesys.com">abalashov@evaristesys.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">The salient quality of a reinvite is that has_totag() == true; it is <br>
handled in the loose_route() section of your config. You want to do the <br>
SDP manipulation in the part below that, where initial INVITEs are handled.<br>
<br>
On 12/9/20 2:47 AM, David Cunningham wrote:<br>
> Hi Daniel,<br>
> <br>
> Removing the sendonly from the INVITE SDP sounds like the most workable <br>
> solution in our case. We'd only want to do it for a new INVITE though, <br>
> not a re-INVITE in a situation where a call is put on hold. Would you be <br>
> able to give an example of such a configuration?<br>
> <br>
> Thanks very much for your help!<br>
> <br>
> <br>
> On Tue, 8 Dec 2020 at 21:56, Daniel-Constantin Mierla <<a href="mailto:miconda@gmail.com" target="_blank">miconda@gmail.com</a> <br>
> <mailto:<a href="mailto:miconda@gmail.com" target="_blank">miconda@gmail.com</a>>> wrote:<br>
> <br>
> Hello,<br>
> <br>
> if the endpoint is not behind a port forwarding nat/firewall (when<br>
> one can instruct the rtp relay to use signaling address), then<br>
> probably you can try to remove the sendonly from the INVITE SDP.<br>
> That will enable rtp from endpoint to doorbell, which may rise<br>
> additional concerns (e.g., privacy) if its is explicitly not wanted<br>
> to happen. But as Alex said in another response, the only way to get<br>
> it work is to make the endpoint behind nat to send a RTP packet.<br>
> Usually the doorbells I encountered so far were accepting incoming<br>
> traffic as well, to discuss/interact with the person ringing on it.<br>
> <br>
> Cheers,<br>
> Daniel<br>
> <br>
> On 08.12.20 05:01, David Cunningham wrote:<br>
>> Hello,<br>
>><br>
>> We have a problem with a SIP doorbell device which sends media one<br>
>> way only, and NAT at the receiving device.<br>
>><br>
>> When the doorbell button is pressed it makes a call to a<br>
>> configured destination. Since the doorbell only sends and doesn't<br>
>> receive it sends the INVITE with sendonly in the SDP, and the<br>
>> destination then replies with a 200 OK with recvonly in the SDP.<br>
>> The problem is that the destination is behind NAT, and its reply<br>
>> contains a private network IP in the SDP.<br>
>><br>
>> Normally Asterisk when nat=yes works around that by adjusting the<br>
>> destination for RTP to be the address it actually receives audio<br>
>> from, however because this device is recvonly Asterisk never<br>
>> receives audio from it. This means Asterisk keeps trying to send<br>
>> the doorbell's RTP to the private network IP which of course<br>
>> fails, and the destination never gets the RTP from the doorbell.<br>
>><br>
>> We haven't found a solution in Asterisk to this, so are now<br>
>> looking to Kamailio which acts as a load-balancing proxy in front<br>
>> of Asterisk for one. For example, maybe we could use<br>
>> fix_nated_sdp, but only on 200 OK's with recvonly.<br>
>><br>
>> Has anyone else encountered this, and are there any recommended<br>
>> solutions?<br>
>><br>
>> Thank you in advance!<br>
>><br>
>> -- <br>
>> David Cunningham, Voisonics Limited<br>
>> <a href="http://voisonics.com/" rel="noreferrer" target="_blank">http://voisonics.com/</a> <<a href="http://voisonics.com/" rel="noreferrer" target="_blank">http://voisonics.com/</a>><br>
>> USA: +1 213 221 1092<br>
>> New Zealand: +64 (0)28 2558 3782<br>
>><br>
>> _______________________________________________<br>
>> Kamailio (SER) - Users Mailing List<br>
>> <a href="mailto:sr-users@lists.kamailio.org" target="_blank">sr-users@lists.kamailio.org</a> <mailto:<a href="mailto:sr-users@lists.kamailio.org" target="_blank">sr-users@lists.kamailio.org</a>><br>
>> <a href="https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users" rel="noreferrer" target="_blank">https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users</a> <<a href="https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users" rel="noreferrer" target="_blank">https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users</a>><br>
> <br>
> -- <br>
> Daniel-Constantin Mierla --<a href="http://www.asipto.com" rel="noreferrer" target="_blank">www.asipto.com</a> <<a href="http://www.asipto.com" rel="noreferrer" target="_blank">http://www.asipto.com</a>><br>
> <a href="http://www.twitter.com/miconda" rel="noreferrer" target="_blank">www.twitter.com/miconda</a> <<a href="http://www.twitter.com/miconda" rel="noreferrer" target="_blank">http://www.twitter.com/miconda</a>> --<a href="http://www.linkedin.com/in/miconda" rel="noreferrer" target="_blank">www.linkedin.com/in/miconda</a> <<a href="http://www.linkedin.com/in/miconda" rel="noreferrer" target="_blank">http://www.linkedin.com/in/miconda</a>><br>
> Funding:<a href="https://www.paypal.me/dcmierla" rel="noreferrer" target="_blank">https://www.paypal.me/dcmierla</a> <<a href="https://www.paypal.me/dcmierla" rel="noreferrer" target="_blank">https://www.paypal.me/dcmierla</a>><br>
> <br>
> <br>
> <br>
> -- <br>
> David Cunningham, Voisonics Limited<br>
> <a href="http://voisonics.com/" rel="noreferrer" target="_blank">http://voisonics.com/</a> <<a href="http://voisonics.com/" rel="noreferrer" target="_blank">http://voisonics.com/</a>><br>
> USA: +1 213 221 1092<br>
> New Zealand: +64 (0)28 2558 3782<br>
> <br>
> _______________________________________________<br>
> Kamailio (SER) - Users Mailing List<br>
> <a href="mailto:sr-users@lists.kamailio.org" target="_blank">sr-users@lists.kamailio.org</a><br>
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> <br>
<br>
-- <br>
Alex Balashov | Principal | Evariste Systems LLC<br>
<br>
Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)<br>
Web: <a href="http://www.evaristesys.com/" rel="noreferrer" target="_blank">http://www.evaristesys.com/</a>, <a href="http://www.csrpswitch.com/" rel="noreferrer" target="_blank">http://www.csrpswitch.com/</a><br>
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</blockquote></div><br clear="all"><br>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>David Cunningham, Voisonics Limited<br><a href="http://voisonics.com/" target="_blank">http://voisonics.com/</a><br>USA: +1 213 221 1092<br>New Zealand: +64 (0)28 2558 3782</div></div></div></div></div></div></div></div></div></div></div>