[Spce-user] Rings once, then disconnects!

Alex Lutay alutay at sipwise.com
Tue Feb 2 03:24:19 EST 2016

Dear William,

Check incoming invite from softphone to Sipwise,
I am strongly believe you will find the same part there.

Sipwise doesn't change SDP part a lot, mainly it is replacing IP
(I believe you have replaced '<PBX-IP>' in SDP part manually, otherwise
it is an error) and limit list of codecs if necessary (turned off by

You can also try to make a call from your softphone through your
Carrier directly and compare invite sent by softphone and Sipwise.

On the first look I do not see anything which can cause 500 on carrier
side here. Was the correct IPv4/IPv6 in <PBX-IP> ?

On 02/02/2016 01:03 AM, William Hilsum wrote:
> These additional lines in the "invite (SDP) packet" from Sipwise to the carrier platform break the connection:
> m=video 32562 RTP/AVP 34
> c=IN IP4 <PBX-IP>
> a=rtpmap:34 H263/90000
> a=fmtp:34 QCIF=1;CIF=1;SQCIF=1;CIF4=1
> a=sendrecv
> a=rtcp:32563
> a=direction:both

Alexander Lutay
Head of Quality Assurance
Sipwise GmbH, Campus 21/Europaring F15
AT-2345 Brunn am Gebirge

Office: +43(0)13012036
Email: alutay at sipwise.com
Website: http://www.sipwise.com

More information about the Spce-user mailing list