he popularity of mobile computing and communications devices can be traced to their ability to deliver information to users when needed. Users want ubiquitous access to information and applications from the device at hand, plus they want to access and update this information on the fly. The ability to use applications and information on one mobile device, then to synchronize any updates with the applications and information back at the office, or on the network, is key to the utility and popularity of this pervasive, disconnected way of computing