Next generation networks are promising ubiquitous coverage and improved service provision to users. This is based on the abundance of available access technologies and the recent efforts on interworking between these different networks in an efficient way. IEEE 802.21 standard is one of these initiatives, providing enhanced handover experience when moving among different access networks. In this paper we will present metrics to
evaluate the performance of these handovers and use the network simulator ns-2 to measure the performance according to such metrics.