3G and WLAN Interworking Security: Current Status and Key

The third-generation (3G) mobile communication systems provide great coverage, complete subscriber management and nearly universal roaming. Nevertheless, 3G systems are subject to the low data rates (2Mbps highest for WCDMA). WLAN (Wireless Local Area Network) provides hot spot coverage with high data rates (reaches 54Mbps while 802.11 a/g), but is subject to short range (reaches 100m the furthest) and lacking a roaming and mobility support. From the users’ point of view, the Integration of WLAN and 3G systems will provide a convenient and attractive way for the user to access network. The users are able to access 3G mobile network while at high speed travel or access WLAN while moving slowly or entering a specific area. However, while integrating WLAN and 3G, there are still some problems that should be considered in terms of authentication and security (such as billing, service continuity and authentication delay). In this article, we focus on the UMTS (Universal Mobile Telecommunications System). First, we review the interworking scenarios and architecture of 3G and WLAN. Then, we review the standardized authentication protocol for 3G/UMTS and WLAN interworking; moreover, we will review some papers related to the security issues and solutions on interworking between 3G/UMTS and WLAN. We also further make some comparisons to these schemes on their features and performance. Finally, we conclude some future works for the interworking between 3G/UMTS and WLAN.