A seamless mobile VPN data solution for UMTS and WLAN users

Mobile virtual private networks (MVPNs) can provide remote users with easy, secure high-speed access to their enterprise network resources. There is a tremendous market opportunity for operators who can meet the needs of these users. Third-generation (3G) systems, such as Universal Mobile Telecommunications System (UMTS), and IEEE 802.11b wireless local area network (WLAN) systems have complementary strengths. For end users, integrating these systems provides ubiquitous high-speed data coverage, continuous selection of the highest possible data rates and seamlessly maintained user VPN sessions when moving between air interface technologies. For operators, they enable integrated billing and offload UMTS network capacity for higher revenue voice subscribers. In this article we discuss interworking architecture for providing integrated service capability across UMTS and 802.11b based networks. We present tight and loose coupling choices for integration, recommend the loosely-coupled interworking approach, and show how it offers a comprehensive and secure transport layer solution across UMTS and WLAN air interface technologies.