The Telecom companies are looking to converged services to replace the lost revenue they used to get from long distance and simple access charges. APIs (Application Programming Interfaces) are the crucial tool used for creating these services. * Detailed coverage of JAIN (Java Integrated Networks) and Parlay, the first open APIs released * Provides software basics for telecom professionals * Thoroughly details object-oriented environments * Endorsed by the creators of JAIN and parlay