Access network discovery and selection in the evolved 3GPP multi-access system architecture

The system architecture evolution (SAE) of mobile networks specified in 3GPP release 8 comprises an evolved packet core (EPC) network to which different types of access networks can be connected. Inter-system mobility management enables users to change the access network while maintaining ongoing data sessions. One important functionality in a 3GPP system is how a mobile terminal discovers and selects available access networks. In this paper we describe the access network discovery and selection functionality used in 3GPP release 8; we explain the differences of the methods applied for 3GPP access networks (GERAN, UTRAN, E-UTRAN), for fixed or wireless non-3GPP access networks (e.g. WLAN, WiMAX), as well as the optimisation used for CDMA2000 access networks. Copyright © 2010 John Wiley & Sons, Ltd.