A standardized abstraction layer, CSTA allows telecommunications applications to operate independently of underlying protocols. It provides a telephone device model that supports compatibility with a wide range of telephone equipment. Originally developed in 1992, CSTA has evolved over the years and became an OSI standard in July 2000. It is currently maintained by ECMA International.
Core Features
CSTA’s core is a normalized Call Control model. Beyond this, it includes Call Associated features and Physical Device features, among others.
Profiles
Implementations of CSTA do not require all features. Profiles, such as the Basic Telephony profile, offer subsets of functionality, including features like Make Call, Answer, and Clear Connection.
Maintenance and Development
CSTA has been continuously refined since its inception. ECMA International oversees its ongoing maintenance and updates.