Centrex 21 emulation for VoIP.
Centrex Chain™ provides business level
Ring No Answer and Busy condition routing.
Originally written for our business VoIP
customers, Centrex Chain™ is a modular
class of service (COS) that has been
integrated for use with other Clarity
classes of service. It is most commonly
used as a "front-end" to the following COS
when live answer is desired before further call
treatment: