SOFTWARE DEFINED ARCHITECTURE CONCEPT - A NETWORK SYSTEM MODEL FOR INFORMATION NETWORKING ARCHITECTURE

In recent years, communication networks have been required to introduce various services and efficient operation of network resources. There have been many discussions about hierarchical abstraction models of network functions and a distributed application platform, such as studies of the intelligent Network conceptual model and Distributed Application Framework in CCITT. On the other hand, communication networks (telecom networks, packet switching networks, common channel signaling networks and intelligent networks) will be integrated in Asynchronous Transfer Mode (ATM) nodes in the future B-ISDN era. Each communication network will be constructed on an integrated transport network. This paper proposes the new concept of "Software Defined Architecture (SDA)", a conceptual model for implementing communication networks and a network system model for describing communication networks. This concept makes possible communication networks that can be quickly constructed in an integrated transport network and dynamically reconstructed in response to traffic fluctuations and node overloads. Using the network system model, a network system is specified by three kinds of specifications: component, frame and implementation. The network system is constructed or reconstructed on the basis of these specifications. This paper reports an intelligent network system as an example of a communication network which applies the SDA concept.