Supporting IP end-to-end QoS architectures at vertical handovers

IP end-to-end QoS mechanisms are quite important for users of real-time multimedia applications. Wireless access systems are widely used also with multimedia applications although the access networks may present heterogeneous technologies and diverse QoS mechanisms. Vertical seamless handover between different wireless systems is possible while the Internet's QoS mechanisms are difficult to integrate into the handover procedures. ITEA's Easy Wireless project develops a new approach to end-to-end QoS in wireless heterogeneous networks. In this paper we discuss how the IP end-to-end QoS architectures can be supported when a seamless vertical handover is executed between different network systems. We focus on analyzing the latest standardized versions of the existing wireless 2/sup nd/ and 3/sup rd/ generation cellular systems together with WLAN or WMAN technologies. Differentiated Services and Integrated Services are compared and Differentiated Services is found to be more appropriate to support widely roaming users.