Study and evaluation on software architecture of ASF & SSF on NGN

On the next generation network, application support functions and service support functions (ASF & SSF) are defined as those that control services. We propose a software architecture of ASF & SSF on real networks. Our architecture has generalized sequence-parts that control communication sessions and provide the application functions with high-level interfaces (IFs), such as Parlay-X, for using these parts. Our challenge is to force high-level IFs for application functions and low-level IFs (signallevel IFs), for example SIP, work in cooperation. Our evaluation results demonstrate that our architecture can reduce the number of states in an application function; therefore, we believe it can reduce the program size of an application function.