A Survey on Vertical Handoff Decision Making in Next Generation Wireless Heterogeneous Networks

Heterogeneous wireless network will be dominant in next generation wireless networks (NGWN). Increasing user demands and the growing interest of service providers to offer diverse applications have motivated the integration of heterogeneous wireless networks which enable the users to move seamlessly across different types of networks and to enjoy anytime, anywhere services. The objective is to determine the conditions under which handoff should be performed. Nowadays mobile handsets are capable of having different network interfaces. There are multiple criteria for handoff in NGWN. Handoff decision algorithm decides the optimal target network by considering a set of decision parameters including available bandwidth, velocity, throughput, monetary cost, security and user preference. One of the technical challenges with this integration and interfacing of heterogeneous wireless networks is handoff decision that is used to choose the optimal network depending upon the type and service requirements demanded by the user's application.