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SPA3102 Disconnect Supervision


I would like to know the usage of:

Regional -> Call Progress Tones -> Busy Tone:


PSTN Line -> PSTN Disconnect Detection -> Disconnect Tone:

are they the same and which one will affect the problem as explained below?

The reason I ask this question is that my SPA3102 don't have problem on disconnect calls form PSTN to SPA3102 - the PSTN caller hangup SPA3012 will also on hook and ready to accept next call.

I have a DP to call forward calls after "PSTN Answer Delay:20" to my VSP's voice mailbox if no one pickup the analog phone.  After PSTN user leave the voice message and hangup, SPA3102 is not able to tear down the call. I can hear the continue recording of Busy Tone in the voice message for a few minutes, immediate dail up the PSTN No. will encounter busy (i.e. SPA3102 is still off hook).  Would this be a correctable issue in my SPA3102 or I have to request the VSP side to look into the problems?

2 Replies 2

David Harper
Cisco Employee
Cisco Employee

No, these are not the same.  The tone definitions under the Regional tab control the tones that the SPA will play out to the attached telephone when dialing/ringing/disconnecting etc.  The tone definition under the PSTN Line tab controls what the SPA will interpret as a disconnect tone on the attached telephone line.  If it hears tones matching the definition in this parameter, then it will assume the remote party has hung up and the SPA will hang up the line.

The behaviour you have described is a classic case of failed disconnect supervision.  It is highly likely that the current configuration for the disconnect tone on the PSTN line does not match what the telco is generating.  If you can attach the contents of this field and tell us what country you are located in, we may be able to determine the correct configuration.  I say 'may' because unfortunately the disconnect tones used vary between countries, between telcos within a given country, and sometimes even between telephone exchanges within a particular telco.  So sometimes it can get a little tricky.  But send through the information I've asked for and we can start figuring this out.



Thanks Dave for the clarification, now I have a better understanding.

I am in Hong Kong and I do "believe" I have configured the correct Disconnect Tone parameters in PSTN Line tab. Here is the screen capture:

and we have standardized the audible tones and ringing pattern between TelCo. Attached with the proposed document.  Please look into the last column in the right hand side of the tables, the "Proposed Alignment" were being adapted for many years among TelCo. and for your information my SPA3102 is connected to HKTC network.

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