grates fixed, wireless and packet-based networks. The JAIN network topology provides carriers with the ability to deploy services on devices inside or at the edge of the converged network, including any Java technology enabled end-user device. Furthermore, support for all the necessary telephony protocols that are used between the different network elements in IN, and IP-based (telephony) networks is mandatory (MAP, TCAP, INAP, ISUP, SIP). A key aspect of the JAIN component architecture is to move the signalling layer away from proprietary switches to MGCs. The API defines a programming interface to the converged networks in terms of an abstract, object-oriented specification. As such it is designed to hide the details of the specifics of the underlying network architecture and protocols from the application pro- grammer to the extent possible. Table 3.3 Parlay VS. JAIN Parlay A generic model of a telecom network A software component factory Provides a model of the network capabilities Provides a set of conventions for building (and means to manipulate the model) software components for the telecom industry Independent of the network internals Can be used by both network and service developers Meant to be used by service developers Both network software (inside the network) and applications Services using Parlay are meant to reside Software (outside the network) can be developed outside the network trust boundaries using JAIN components Understanding Changing Telecommunications - Building a Successful Telecom Business MP-3 - MPEG-1, layer 3. A standard for compression and storage of large sound files. OSA - Open systems architecture. A concept defined by 3GPP and Parlay. It spec- ifies services available to applications on application servers over standardized pro- grammable interfaces. XML - Used for exchange of data between applications. It is a markup language much like HTML. XML is designed to describe data in a universal format on the web. XML is used for documents containing structured information. It enabl