Peer-to-Peer (or P2P) systems are distributed systems that provide high quality information sharing services to many users distributed over the interconnection network. To extend a P2P network system with the mechanisms of distributed computing, we developed a flexible JXTA-based P2P network interface and architecture, called JXTPIA. We have implemented JXTPIA network, Homework Distribution module, Trigger Distribution module, and Data Sharing module. The JXTPIA system provides the basic functionalities for distributed/Grid computing, such as resources allocation, task scheduling, task assignment, network structure constructing and maintenance, and data sharing, etc. Experimental results show that it executes the large applications efficiently. Further performance evaluation and experimental data analysis will be conducted.