where is fmg/telephony/1 stream is orginating?

fmg/telephony/1 is created by FMG; It is formatted as fmg/<serviceName>/<uniqueDigit> . Apart from <serviceName> name of this stream is purposefully kept unconfigurable.

However, if your application required providing a constant or configurable streamName for various puposes like "broadcast" or "fileRecording" there is a pretty standard way out.

1) Stream class in Flash Media Server's Server-side actionscript may be used to create a new stream with customName.

2) Set fmg/telephony/1 as source for the newly created stream in step 1 above.

3) use your custom streamName to while subscribing  from Flash Player or while recording on FMS.

An older thread might help:http://forums.adobe.com/thread/783641

Documentation of FMS Stream class: http://help.adobe.com/en_US/FlashMediaServer/3.5_SS_ASD/WS5b3ccc516d4fbf351e63e3d11a11afc95e-7e42.html

A typical change in FMG's sample telephony application might look like following code snippet.

application.s=Stream.get("myCustomStreamName"); // Initialising a custom stream from FMS server side. Creating only one stream while assuming that there will not be more than one call running; otherwise, the code will have to create and manage multiple such streams. application.onLeg{ // existing onLeg handler in default telephony application. . . . if(s) {    s.play(info.incomingStream); // info.incomingStream is the name of stream published by FMG; e.g. fmg/telephony/<i>    trace("Now use the streamame: 'myCustomStreamName' to record or subscribe as a stream with constant name"); } . . }