摘要

P2P system is a very active research field due to the popularity and the widespread use of these systems today and their potential use in future. P2P networks are loosely coupled system without central control where peers have more autonomy. Therefore transaction management is crucial to applications such as e-commerce, process support systems etc. This study intends to utilize more semantics of application in transaction management for P2P environment. A transaction description model based on Colored Petri Net (CPN) is proposed. In this model, a transaction is composed of subtransactions that have been put together as building blocks according to the semantics of application. And transaction is denoted as a CPN, Transaction Net (TN) that is the combination of some sub-nets and the sub-nets are TNs of its subtransactions. Operators to construct a transaction from known ones as subtransactions, including sequence, concurrency, iteration and alternative are defined formally. Using this CPN, relations of subtransactions can be illustrated by the structure of TN and dynamic properties of transaction can be simulated by executing the model. Properties of the model are analyzed. Algorithm to execute a compound transaction is presented also.

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