Using a trusted WLAN network to offload mobile traffic and leverage deployed broadband network gateways

This paper introduces the concept and architecture for the Alcatel-Lucent solution to wireless local area network (WLAN) offload in a case where the WLAN network can be considered as trusted by the home operator of the user. Leveraging up-to-date WLAN access points (APs) that provide both support for strong user equipment (UE) authentication - Universal Subscriber Identity Module (USIM) based- and ciphering (AES-based), WLAN access can offer "trusted" access to the Evolved Packet Core (EPC). This trusted access to the EPC can provide Internet Protocol (IP) address preservation when the terminal moves between 3rd Generation Partnership Project (3GPP) access and WLAN access without requiring the UE to support IPsec tunnels to the EPC or Dual Stack Mobile IP version 6 (DSMIPv6). A WLAN gateway (WLAN-GW) acting as an edge router for the UE is able to get policies from the home operator's authorization, authentication, and accounting (AAA) server at UE authentication, and based on these policies, to either send the user traffic to the EPC anchor point - the Packet Data Network Gateway (P-GW) - or to offload such traffic, for example, to the Internet. © 2012 Alcatel-Lucent.