An adaptive data object service for pervasive computing environments

Workstations and PCs typically are rich in resources, in contrast to palmtop devices, which are generally quite limited. This disparity offers challenges to integrating these heterogeneous devices into a single distributed system. Services must be available to each device, but it may be necessary to modify certain services if the connected device does not have the desired resources. A key component of many distributed systems is remote access to data. Traditional distributed file systems are typically rather static and are not able to adapt to the current available resources of the devices involved. Data files are treated as continuous streams of bytes and the interfaces to access them are designed for unstructured data; they simply transfer buffers of contiguous data. Providing modality and adapting content using these interfaces proves difficult. In this paper, we present an adaptive data object service for pervasive computing environments using distributed objects. Data is manipulated through an object-oriented interface based on containers and iterators. The interface is also used to model data operations, conversions, and proxies. The system is aware of its environment and can instantiate objects in the proper locations to optimize performance.