The present invention provides improved techniques for managing storage
resources, such as disk drives, I/O ports, and the like in a network
based storage system according to a user position within the network.
Embodiments according to the present invention can provide a relatively
high performance storage access environment for the mobile users moving
around a wide area. For example, in one applicable environment, there are
several data centers in the wide area, and each data center has a local
storage system that is connected to the other storage systems through a
network. Copies of a user's volume can be made in some of the storage
systems. A remote copy function is utilized for making real time copies
of the user's volume.