With the availability of various wireless link-layer technologies,
such as Bluetooth, WLAN and GPRS, in one wireless device,
ubiquitous communications can be realized through managing
vertical handoff in the environment of wireless overlay networks.
In this paper, we propose a vertical handoff management system
based on mobile IPv6, which can automatically manage the multiple
network interfaces on the mobile device, and make decisions on
network interface selection according to the current situation.
Moreover, we apply our proposed vertical handoff management with
JPEG-2000 codec to the wireless application of map image access.
The developed system is able to provide seamless communications,
as well as fast retrieve any interested map region with any block
size, in different resolutions and different color representations
directly from the compressed bitstream.