An up-to-date survey of location and transaction management in mobile database systems

Abstract

Mobility attracts many developers and system designers; it will give us the ability to use our computers with no physical limitations with respect to connections. This thesis will try to introduce the main concepts that define mobile computing in our days. It will identify the challenges that face mobile computing and their impact on current developments in this area. Location management and how the cellular networks function is defined and described. We will conduct a comparison between protocols in location management with respect to network messages and database operations. In the IS-41 model and the Forwarding pointer model we proposed some enhancements to the protocols used, we conducted a cost study on the models with respect to network messages and database operations. In the Hierarchical model, we also proposed to use the distance based update mechanism after we conducted an analysis on the cost of update in the hierarchical model. We proposed to use an adaptive location management model to accommodate for the various requirements of mobile users and their behavior. Also in this thesis, we described the impact of mobility on Transaction management. We were able to put a set of characteristics that define mobile transactions after studying different models with the emphasis on their ACID properties. Our new model introduces the concept of an agent located at the mobile support station to control and manage the transactions issued and directed to the mobile host; a global transaction manager was also defined to interact with the mobile transaction manager responsible for the mobile part of the network. We also introduced the idea to use mailboxes for the mobile hosts as a central repository to be used by the system to maintain the well processing of the transactions and enable the system to accommodate for the movement of the mobile unit. We also defined the new set of queries and data that might be found in mobile systems and their impact on our model with respect atomicity, consistency, isolation, and durability.