|Open Architecture Computer Telephony Servers and Tools|
One Platform - Muiltiple Solutions - Imagine a modular voice, fax and data telecommunications system that can support from 4 to 2,400 lines per machine, and that is scalable over multiple machines to support many thousand lines. Imagine that the system is customisable using high productivity Rapid Application Development (RAD) tools such as Visual Basic, and that you can actually update your applications while the system is live, without interfering with any applications already running. Then imagine that the whole system is maintainable from a graphical interface, even over a dial-up connection. You don't need to imagine any more, we have already created it .
System of Selectable Modules Both the hardware and software are modular.
These Modules customise the CallHandler to the individual user's application.
This could be a Voice Mail System, Audio Conferencing System, or a complete
integrated Fax/Voice/Email Messaging System.
Visual BASIC/C++ Application Modules plug In at the top level.
Devices, Managers, Services
CallHandler Structure CallHandler is a modular system comprised of a collection of COM objects. There are three types of object: Device, Manager and Service. Device objects control external resources such as telecom channels, DSP channels, and external TCPIP links, Manager objects control system wide resources, and Service objects are the system services.
A Device is the core element of the CallHandler. A Device is a COM software object which provides Resources to the CallHandler. The Device object usually controls PC cards, for example a telephony card, or a DSP card. But, the Device can also provide software (or virtual) Resources, for example LAN service control channels, or call transfer channels.
A Resource is a facility that the Devices provide to CallHandler Services. For instance the Call Control Device provides telephone lines, the DSP Device provides DSP channels. The allocation of Resources in the CallHandler is managed by one central Manager, the Resource Manager.
A Service is a program module that is plugged into the CallHandler to provide particular services, for example the IVR service, FAX service, Voice Mail service etc. The Service module is a COM DLL object which can be written in any language that supports COM for example Visual Basic 6, C, C++, Perl, Java etc. The CH-Developer kit provides all the tools for programmers to develop their own Services.
To make a telephone call and play a message, a telephone Resource, needs to be connected to a DSP channel Resource. A Route is the connection between these two Resources across the telephony bus (the MVIP, SCBUS, or H100 Bus). Also, if there are any messages passed between the two Resources, for example if the caller hangs-up on the telephone line, the DSP channel needs to be told to stop playing the message. So, an Event Route is established between the two Resources, so that messages can be passed between them.
See Also [Primary Rate versus BASIC Rate & Card Configurations]