A Transaction Model for Mobile Atomic Transactions

A mobile transaction is a distributed transaction where at least one mobile host is involved. In this situation, disconnection and location dependency (the movement problem) will normally be a problem even if relaxed atomicity is used. In this paper, an update propagation tool is used to manage remote updates that must be executed to fulfill the atomicity property. The update propagation tool resubmits messages until they have been processed (committed) in the receiving location. However, in case of disconnection or overload, many messages to a mobile client may be submitted in vain. Therefore, the server should only activate ´push update propagation´ a few times. Later, when the connection has been reestablished, the mobile client can activate a ´pull update propagation´ asking for stored messages that have not been pushed successfully yet. By integrating the update propagation tool with mobile IPs and/or SOA services it is also possible to solve the location dependency problem.