Can someone tell me when it's best to use CVLAN, or DLG. I see that they are both using the ASAI protocol and that they have more or less the same functionality. DLG is using Direct ASAI messages over a TCP/IP tunnel protocol and CVLAN uses a client server architecture to send message in a proprietary CVLAN format. Also CVLAN uses a client library.

As a second question: How do these services relate to the TSAPI interface?

Think of DLG, CVLAN, and TSAPI as a progression in time of the same core set of ASAI capabilities.

Since applications were written to DLG it continues to be supported, however we do not recommend starting new development using this interface. You will spend a lot of time implementing drivers that are alreay built with CVLAN and TSAPI.

CVLAN was built to provide these libraries and simplify some of the complexities that arise from dealing with the protocol level interface that DLG provides so developers could concentrate on building the app and not on the interface to Communication Manager (well back then Definity).

TSAPI is also built on top of ASAI, but provides conversion from ASAI to CSTA (international standards). It provides a similar set of services that the propritary CVLAN interface provides.

Just to complete the story, JTAPI is built on top of TSAPI (which provide a C language interface) and provides a similar set of services that TSAPI provides through a Java API.

Finally Avaya does not recommend starting a new application using CVLAN either. We would recommend using TSAPI or JTAPI as the starting point for new development work.

Thanks for your interest/question.

John

Thanks for clear explanation