[Freeswitch-users] Responding to INVITE with 180 vs 183

[Michael Jerris]

I doubt it has anything to do with 180vs183.  Check for nat issues in the trace that isn't working.

> On Feb 10, 2015, at 2:55 PM, Ben Hood <0x6e6562 at gmail.com> wrote:
> 
> Hi all,
> 
> I'm wondering what influences Freeswitch's signalling response when it
> responds to an INVITE.
> 
> In some instances it appears to follow this sequence:
> 
> Peer -> INVITE (SDP) -> FS
> Peer <- 100 <- FS
> Peer <- 183 (SDP) <- FS
> Peer <- 200 (SDP) <- FS
> Peer -> ACK -> FS
> 
> Which leads to a successful bridge between two legs.
> 
> But in other instances it appears to follow the sequence:
> 
> Peer -> INVITE (SDP) -> FS
> Peer <- 100 <- FS
> Peer <- 180 (SDP) <- FS
> Peer <- 200 (SDP) <- FS (1st attempt)
> Peer <- 200 (SDP) <- FS (2nd attempt)
> ....
> Peer <- 200 (SDP) <- FS (nth attempt)
> ....timeout
> 
> I'm not 100% sure whether the remote peer (itself a SIP trunk) doesn't
> like the 100/180/200 sequence (as opposed to 100/183/200), so I need
> to find that out for myself.
> 
> But I am wondering what factors influence Freeswitch's decision of
> what sequence signals to send in response to an INVITE.
> 
> Any pointers appreciated,
> 
> Ben