HDD3M: A New Data Communication Protocol for Heterogeneous Distributed Mobile Databases in Mobile Ad Hoc Networks

Three data communication methods can be provided in a MANET: data broadcast, data query, and peer-to-peer messaging. The formation of heterogeneous distributed mobile databases within a MANET that allows people to submit queries or transactions is becoming a reality. Previously, the DD3M data communication protocol (distributed database with 3 communication modes) has been proposed for providing all three data communication modes in the network region and integrating heterogeneous distributed mobile databases in MANETs that allowed mobile application to view this separate non identical databases as one integrated database and adjusted node disconnection and reconnection through periodic synchronization. However, database transaction services were not supported. For managing real-time database transactions in MANET some issues must be addressed (host mobility, power limitations, real-time constraints imposed on transactions and frequent disconnection and network partitioning ...). This paper extends the previous work on DD3M by using a transaction management technique in the HDD3M ( heterogeneous distributed database with 3 communication modes) protocol that allows managing real-time database transactions in MANET and reduces the number of transactions missing deadlines while balancing the power consumption by the mobile hosts in the system. In this heterogeneous distributed database framework mobile servers comprise data directories (DDs) that gather and store the schemas of mobile databases running on detected mobile devices in the service cycle. DDs inform the requesting node whether a submitted transaction is answerable from participating mobile database nodes or not. Also this protocol allows mobile nodes of the architecture to exchange messages for the purpose of executing the submitted transaction against the heterogeneous distributed mobile database and then returning the results.