[Asterisk-Users] Re: Strange Problem

[Stephen R. Besch]

Asterisk Learner wrote:
> 
> 
> I am experiencing a strange problem and wanted to know if someone has 
> faced any similar issues or could provide me with a way to counter this 
> problem. I am in the process of experimenting with asterisk and trying 
> to setup a basic functional system. I have one TDM400P (single port) and 
> one X100P. I am using one analog phone connected to the TDM400P and I 
> also have a couple of Xlite SIP phones configured. I can make calls out 
> to the PSTN and I can also receive calls.
> 
>  
> 
> The problem happens when someone from the outside (PSTN) calls the 
> Asterisk box. I have asterisk configured to forward the call to Zap/2 
> (analog phone). Zap/2 rings and I can talk to the person on the other 
> end but if I hang up first then the other end does not see as the call 
> being hung up. Asterisk CLI shows that Zap/1-1 (FXO) hungup but for some 
> reason the other end thinks that the call is still up and does not 
> disconnect unless the person hangs up himself. The confusing part is 
> that if I initiate the call then this problem does not happen.
> 
>  
> 
> Can someone tell me what is happening and how to resolve this issue?
> 
>  
> 
> Thanks
> 
>  
>
On analog lines, the central ofice switch will signal that the remote 
end hung up the call, if I recall correctly, either by dropping loop 
current or using a brief polarity reversal. There may be other means as 
well.  You need to make sure that you are using the correct settings to 
sense this properly.

The reason you don't see this when you place the call is that, 
obviously, your end has no trouble determining when you have hung up, 
regardless of setting that affect the detection of the remote end 
hanging up.

Stephen R. Besch