Towards the Next Generation Network : The Softswitch Solution
Karl‐Johan Grinnemo, Anna Brunström · 2006
Over the course of the last fifteen years, the telecommunication market has undergone dramatic changes. In the beginning of the nineties, the market essentially comprised a number of national monopolies. Today, yesterday's monopolies are under siege, and the incumbent operators face strong competition from newly established operators. Furthermore, in recent years broadband-based VoIP providers have entered the telecommunication market as worthy contenders to traditional operators. To be able to survive and thrive in this new, much more competitive, market, traditional wireless and wireline operators have to reduce their capital and operational expenditures. They also need to provide new revenue-generating applications and services. To this end, a large number of traditional operators has replaced, or seriously consider to replace, their legacy circuit-switched fixed and cellular core networks with IP. As a first step in the migration from circuit-switched technologies to IP, the softswitch solution has evolved. This report provides a comprehensive treatment of the softswitch solution from a technical viewpoint. Additionally, the report concludes with a brief discussion of the migration steps following the softswitch solution. In particular, an overview of the 3GPP IP Multimedia Subsystem (IMS) is given.