Telephony developers working in VoIP, PBXs, VoIP gateways, phones, modems and other PSTN technologies that are developing products internationally have to know the varying international call progress tones
that differ from country-to-country. Of course, figuring out the disconnect or other progress tones isn't that difficult. Sure you could discover each progress tone's by recording the tones to a .wav file and then use a sound editor program to figure out the exact Hz -- but why go through all that trouble?
You can just head on over to 3am Systems
and search their centalized call progress database to get an instant answer. They call their 'World PSTN Tone Database'
, which will not only tell you the proper Hz and cadence, but it will even display the proper Zaptel/Asterisk string for easy copy/pasting into your Asterisk system. They also have a Sipura/Linksys mode that will display the proper configuration string for use on Sipura/Linksys equipment. You can search on a specific call progress tone (acceptance, dialtone, disconnect, busy, fast busy, etc.), search for tones used in a specific country or search a combination of the two.
According to Brian E. Cauchi at 3am Systems, "The whole thing started as an excuse to experiment with Web Hosting
. In a few months the site has outgrown the server’s bandwidth, and users seem to love it, judging from ‘frenzies’ some of our visitors go into once they stumble upon our site. Many of our visitors visit because they are trying to configure regional settings for their VoIP gateways. Encouraged by the response, we’ve gone to some length to mine, sift and refine our data."
PHP and MySQL? Nice! Two of my favorites. In fact, this blog runs on MySQL and I've looking to add PHP support to TMC's blogs in the near future, as part of my "fun" project to migrate MovableType from Windows IIS to Linux.
In any event, the 'World PSTN Tone Database' is something that every telecom developer and telephony professional should have in their arsenal! Good stuff! p.s. The Hz info is available without registering, but you can also download .WAV sound files for the individual tones. But for the WAV files you have to register first. Pretty cool to get a recording of the actual progress tones.