We discuss and prove the correctness of a transaction model for mobile ocmputing.In our transactin model,we incorporate a prewrite operatin (before a write) which does not update the state of a data object but mades visible the value that the data object will have after the commit of the transaction.Once a transaction read all the vlaues and declares all the prewrite values.it pre-commits at mobile host.A pre-committed transaction's prewrite values are made visible both at mobile and stationary hosts before the final ocmit.Thus,increases data availability.A pre-committed transaction's remaining execution (i..e,writes on database) is delayed and shifted to the modbile ser ice station to reduce the ocmputing expenses at mobiel host.We have analyed various cases of running transactions ocncurrently both at mobile and stationalry hosts.Wfe hav eproved tha tour algorithm produces only erializable schedules.
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