Separation of responsibilities between application servers and media servers in NGNs: A practical approach

Abstract

In this paper we deal with the separation of concerns among the entities involved in multimedia sessions in Next Generation Networks (NGNs). In particular, the focus is on the explicit separation of responsibilities between Application Servers, which are in charge of the services application logic, and Media Servers, whose task is instead the low-level manipulation and delivery of media streams. The paper describes the standardization proposals coming from both the 3GPP and the IETF from a very practical point of view, and presents the reader with the currently only available implementation of the MEDIACTRL architecture. Furthermore, the paper is also devoted to describing some typical multimedia scenarios from the presented perspective, by providing an in-depth analysis of the related sequence diagrams and protocol messages. © 2008 Springer-Verlag Berlin Heidelberg.