[Freeswitch-users] What happen when leg-a & leg-b are on SIP/TCP and one get a socket disconnection during a call?

[Fabio Pietrosanti (naif)]

Hi,

sorry for using the so big subject, i am experiencing some strange 
behaviour i am going to enter more in depth debugging in the next weeks.

I have the following situation:
- A call getting established
- both peers are using SIP/TLS over TCP
- leg-b get disconnected at TCP level (such as WiFi disconnection or 
just a TCP hard reset by a NAT device reloading it's rules)

In such condition i noticed, but still need detailed investigation, that 
FS does not detect that leg-b TCP socket died, thus notifying 
immediately leg-a that the call cannot be completed.
FS instead, it seems from log/tcpdump observation, wait until the 
various SIP timer expire in order to provide back to leg-a error that 
the call cannot be completed.

If it's that way, it would be a nice improvement, when a SIP/TCP or 
SIP/TLS client get a TCP disconnect, to immediately react on the other 
leg of the call by notifying the proper SIP error, because the layer4 
(SIP) connection is lost due to a layer3 (TCP) connection break.

Is this something feasible/reasonable?

Fabio