NSF Grant IIS-0208741 Collaborative Research in DAta in Your Space (DAYS)

Project Summary

Wireless communication is one of the essential components of the information dissemination discipline and its role will continue to dominate the mobile computing world of the future. In fact the wireless discipline will define the information dissemination and processing infrastructure for the recent future. This challenge can be easily met with the recent advances in wireless technology, which make it possible to overcome the spatial and temporal constraints in data dissemination and their processing. We envision a scheme which can create an information management system for every user anytime anywhere in space. The creation of such a system will be transparent to the user. Thus, a user (a company or an individual user) from anywhere or at any time can {\em pull} the desired information from the space, process it, and {\em push} it to the desired place in the space for future use or to be shared. We call our system DAYS (DAta in Your Space). In this proposal we investigate a major problem, which is data dissemination and a number of essential less major problems such as concurrency control, data caching, application recovery, and data indexing. For data dissemination our approach is unique. Our research expands on previous research, particularly that of the {\em Broadcast Disk}. We view space (air all around us) as both a persistent storage medium and also as a data dissemination resource. Our space is actually a collection of wireless channels, which we propose to use for storing data by continuously pushing (transmitting) the data to the wireless users. However, the traditional broadcast approach is not amenable for update from the wireless users. Thus we develop techniques which allow mobile users to update the data source via more traditional techniques while pulling it from the broadcast. The major goals of our research include:

• Development of a unique concurrency control technique which allows a wireless user the ability to perform a transaction by combining a read through the broadcast and write through a special mobile transaction.
• Design of a broadcast server/mobile station coupled architecture which ensures a global broadcast coverage (as opposed to local).
• Techniques to predict mobile user movement and to move a user's data to future predicted broadcast servers prior to his arrival in a broadcast cell.
• In DAYS, a mobile user must be able to determine what local broadcast channel contains his desired data. We will investigate several approaches to satisfy this and recommend the best.
• The contents of these broadcast channels will change depending upon the requirements of the users and also of DAYS. We will investigate efficient schemes of content replacement strategies for achieving the highest hit rate.
• It may be necessary to duplicate or replicate broadcast contents to more than one dedicated channel. This may be decided on demand or for improving availability. We will investigate schemes for distribution of data in DAYS.
• To achieve continuous data availability, we must have an efficient recovery scheme. We will investigate recovery situations and develop recovery protocols for recreating the normal execution environment.

This investigation will promote an innovative use of wireless technology in managing information in the space. It will take the information processing from the confined environment to the open space, which will become a universally accessible reliable storage medium and a global information processing arena.

Reports:

• Report 2003 (html)

• IDM Report 2003 (html)