[Asterisk-Dev] CSTA interface comments

[John Todd]

I've recently started to get involved in proprietary controls for 
existing PBX platforms, and I've run across a standard which may have 
some interest to those of you on this list.  The CSTA (Computer 
Supported Telecommunications Applications) seems to be very similar 
to (depending on your views) the Manager Event interface, or AGI. 
While I don't suggest that either of those two existing interfaces is 
sub-standard, I would love to hear from anyone with more experience 
with CSTA about why it is a better or worse protocol for interaction 
with Asterisk.  It seems (again) that there is a standard that exists 
for interfacing a PBX (or other telephony switching system) to 
external applications on a different platform.  Perhaps even some of 
the established applications support CSTA in enterprise environments 
might be able to be linked to Asterisk quickly via this method (I 
know that Envox http://www.envox.com/ uses CSTA - anyone else?)

While there is very little "real example" data in these documents, 
the documentation is at least reasonable.  I'd love to see a human 
(versus an ITU participant) explain how this actually works, and 
provide a serial data exchange in a ladder diagram for a few examples.

A CSTA interface module might be useful for patching Asterisk into 
existing platforms that use CSTA controls; places that Avaya, Nortel, 
Siemens, and others now have exclusive domain.  A "swap-out" is a lot 
more appealing than saying "You'll have to write a glue layer to 
interface to this new system."

http://www.ecma-international.org/activities/Communications/TG11/cstaIII.htm
http://www.dragonnorth.com/tsapi/reference.html

JT