QoS Assurance of Next Generation Network (NGN) Applications

A Next Generation Network (NGN) application is an application that provides a value–added service seamlessly across an integrated network consisting of a combination of packet–switched, circuit–switched, wireless and wireline networks. Such an application is likely to be developed using a set of open, standard APIs. These APIs provide a level of abstraction to shield the application programmers from the underlying complexities of heterogeneous networks. As a result, these APIs facilitate rapid service development by allowing an application developer to focus on the functionality (that is, what is provided), rather than on the implementation (that is, how it is provided). The importance of open, standard APIs in encouraging the growth of a community of application developers is evident from a number of initiatives to develop such APIs and environments providing these APIs. These initiatives include JAIN [2]TM,1, OSA/PARLAY [3], and 3GPP [1]. Although these APIs facilitate rapid service creation by eliminating the need to understand the peculiarities of the underlying network infrastructures, the quality assurance of these services will require a service developer to become fully cognizant of such details. This requirement, which is primarily due to the lack of a consistent methodology for quality assurance, significantly mitigates the advantage of decreased development time gained by using open, standard APIs. A systematic framework for QoS assurance based on open, standard APIs provides an integrated approach for rapid service creation as well as quality assurance of these services and is the focus of this paper. The QoS assurance framework described in this paper is based on the use of JAINTM,2 APIs.