[Spce-user] calls dropped after 30 seconds

Andreas Granig agranig at sipwise.com
Tue Jul 24 11:57:38 EDT 2012

Hi Guys,

On 07/24/2012 04:49 PM, Daniel Speichert wrote:
> I have exactly same problem, my calls are dropped after exactly 32 seconds.
> I haven't found a way to fix that and I don't think it's a SIP ALG problem.

The system is tested and deployed in production with dozens of clients,
so it's unlikely that it contains such an obvious flaw. However, we've
seen LOTS of broken clients and LOTS of setups with routers or other
intermediate hops messing with SIP messages, and *every* SIP ALG I've
seen so far is broken.

In this particular case of Jirka, the SPCE sends a 200-OK with the
Contact URI "<sip:ngcp-lb at SERVER_PUBLIC_IP:5060>", but the client sends
back an ACK with a Request URI "sip:ngcp-lb at crypto2-private:5060". Do
you spot something? Yeah, exactly, someone is messing with the SIP
message horribly somewhere. Either the client, which must take the
Contact URI and put it into the R-URI of the ACK *unchanged*, or maybe
the client already gets the Contact-URI in a modified way, so something
in-between the way from the SPCE to the client tries to be clever.

In any case, if you want a quick and proper answer to your issue, please
provide a full trace (INVITE, 1xx, 2xx, ACK) in an unmodified way with
all the IP and port infos intact (e.g. copy/paste the output of
ngrep-sip, or even better, provide a pcap taken from tcpdump). Otherwise
it's really hard to reconstruct your behavior.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 900 bytes
Desc: OpenPGP digital signature
URL: <http://lists.sipwise.com/pipermail/spce-user_lists.sipwise.com/attachments/20120724/545fc79f/attachment-0001.asc>

More information about the Spce-user mailing list