Due to the growth of user demands and the limitation of third generation (3G) mobile communication system, the need of fourth generation (4G) is expected. Due to the lot of features in 4G, it is better than 3G networks, some features of 4G like high speed internet, fastest data transfer, user can access internet anytime from anywhere. It does basically include the terminal ability that is different types of wireless services at anytime and anywhere. The fourth generation (4G) network will be a heterogeneous network. Here we also work on obtaining the best handoff which includes vertical handoff and horizontal handoff.