A Host Based Autonomous Scheme for Seamless Vertical Handover

In this paper we suggest a host based, end-to-end selfreliant scheme for handover in heterogeneous network environment. It directly involves the correspondent node in the handover process. The proposed scheme imitates the Network Address Translation. It maps a logical address to another logical address. It modifies the address information in the header of the packet while it is in transition. In principle the process is identical to the NAT box operation, but the goal is different. While NAT is primarily used in conjunction with masquerading to hide the private IP address space, HaMAT works in conjunction with MIH and serves to hide the IP address change of the mobile node encountered due to the vertical handover. HaMAT is a functional entity just like Media Independent Handover Function, and it resides inside the Mobile Node and Correspondent Node. By eliminating the need for rerouting, tunneling and route optimization as required in Mobile IP, HaMAT achieves high performance results in terms of handover delay, end to end packet latency, jitter and the overhead involved. The service disruption time for HaMAT is as low as 10 msec compared to reported handover delays of 260 msec and 1 sec for MIPv4 and MIPv6 respectively. Streszczenie. W artykule zaproponowano bazujący na hoście schemat przełączania typu handover w niejednorodnym środowisku sieciowym. Schemat imituje Network Address Translation i mapuje logiczny adres orasz modyfikuje nagłówek w pakiecie. (Bazujący na hoście autonomiczny schemat przełączania typu handover)