What is java api? What's in it? How to use it

Using application programming interface (API) to build services is the key technology to realize the open service structure, and it is also one of the main characteristics of the next generation network that is different from the traditional telecommunication network. At present, the open service API standards for the next generation network mainly include Parlay/OSA API jointly developed by Parlay organization, 3GPP and ETSISPAN, and JAIN API launched by SUN Company on the Java platform.

Parlay API is an application programming interface defined by Parlay organization, which is convenient for service developers to quickly create telecom services. Since the establishment of 1999, Parlay has formulated four versions of Parlay protocol. Open Service Architecture (OSA) is a multimedia service framework developed by 3GPP, and Parlay is selected as its open service interface API. Parlay/OSA API combines the two and is independent of the specific implementation technology, and can be applied to the service provision of fixed network, mobile network and next generation network. It does not depend on the specific implementation language, and can be implemented in various languages such as C, C++ and Java. A perfect authentication and authorization mechanism is defined to support third-party applications.

Parlay/OSA API is located between Parlay gateway managed by network operator and application server managed by service provider. Parlay gateway shields the application server from the technical implementation details of the lower network, so that the application server can uniformly access the network capabilities.

Parlay/OSA API includes two types of interfaces: business interface and framework interface. Business interface provides an interface for applications to access network capabilities and information, while framework interface provides necessary support for the security and management of business interfaces. Business interface ensures that users can access traditional networks, such as call control, call management, message sending, user interaction, etc. The functions provided by the framework interface include business registration, business reservation, business discovery, authentication, authorization and comprehensive management.

JAIN API and Parlay/OSA API have similar design ideas and complementary functions. It is implemented in a specific Java language and defines a relatively complete network protocol API for accessing various networks. At present, the Parlay/JAIN joint working group is working on the integration of the two.