Review of Handoff Technique Used for Wireless Heterogeneous Networks

In the Today’s global telecommunication network, the introduction of heterogeneous wireless networks has caused a revolution in the telecommunication systems. Vertical handoff is a technique using the interface switching mechanisms to enable transparent roaming across the various networks. Handoff Occurs when a mobile terminal switches from one network to another (e.g. from WLAN to CDMA OR VICE VERSA).The handoff, in which users switch between networks under diverse technologies, numerous factors should be considered in order to increase the effectiveness of the network. In this paper, we provide short review of vertical handoff technique, on the basis of Received Signal Strength (RSS) and the interface switching mechanisms to enable clear nomadic across the access networks. We compared different path loss models like okumara-hata model, cost-231 hata model and ecc-33 model.