With recent technology advancements mobility support is one of the major needed parameters by any wireless or mobile networks. Continuous mobile movement from one cell to another or from one network to another requires continuous mobility support. Previously, tunneling protocols employment was the technique to support UE's inter or intra network mobility. More specifically, GRE, GTP, MIPv6 or PMIPv6 were employed for mobility support. In tunneling encapsulation of one protocol over another protocol is performed to deliver IP packet during inter network or intra network handover. In terms of usage scenario of each tunneling protocol, tunnel establishment, data transfer and tunnel release, an overview and comparison of tunneling protocols is presented in this paper. 3GPP and WLAN interworking, and GAN based usage scenarios and supported tunneling mechanisms has been discussed. Some insights regarding security, multiplexing, multiprotocol and packet sequencing support are also provided for each tunneling protocol.