Methods for Multimedia Service Adaptation in Next Generation Networks

dovers between different wireless access technologies provide seamless roaming during active multimedia sessions. The quality of these multimedia sessions, as well as the quality of user experience, depends on the network handover policies, link layer characteristics, and codecs used in the respective networks. Even though extensive research has been carried out on seamless mobility, a thorough analysis of user perception of this aspect is still missing. Knowledge of user perception is however necessary in order to successfully design and further improve mobility management solutions for always-on multimedia services. We present an NGN testbed and an approach for mapping user experience to network conditions, focusing on phenomena caused by a user roaming across diverse wireless technologies. Current experiments address the quality of Voice over IP in Next Generation Networks, as an example of multimedia sessions. These define when a network handover should be scheduled in order to reach optimum quality for the user. I