A secure mobile IP implementation for windows-based wireless LAN stations using special network drivers

As wireless LAN is widely deployed, it is desired to support mobile IP for wireless LAN stations such that they can keep sessions alive when a change of wireless LAN environment happens. However, currently it is difficult to add secure mobile IP functions to windows-based wireless LAN stations, because it usually requires modification of windows components, a very troublesome task for independent developers. This paper proposes a special network interface driver programming method, called iDriver technique, to solve this problem. It is a generic method that enables independent developers to implement kernel-level IP-based protocols in network interface drivers to enhance operating systems that do not have these protocols built in their kernels. Using iDriver technique, this paper implements a windows-based secure mobile IPv4 software system without modifying any windows component. It consists of a mobile client driver and a home agent driver. The mobile client driver is responsible for supplying a fixed IP address to windows, monitoring change of wireless LAN environments, applying an IP address from a new wireless LAN, reporting it to the home agent driver, and tunneling encrypted IP packets to/from the home agent driver. The home agent driver is responsible for tracking location of wireless LAN stations, tunneling encrypted IP packets to/from them, and relaying IP packets between them and their correspondent IP nodes. Both drivers can be distributed and installed as stand-alone software products for windows operating systems.