XtremWeb-HEP (XWHEP) is a middleware permitting a distributed data processing infrastructure (grid computing) to deploy . XWHEP belongs to the so-called Cycle Stealing family that uses idle resources. Like some other grid middleware stacks, XWHEP uses remote resources (PCs, workstations, PDA, servers) connected to the Internet, or a pool of resources inside a LAN. Participants in an XWHEP infrastructure cooperate by providing their computing resources, such as processor, memory, and/or disk space. XWHEP is a lightweight grid middleware. It is a Free Software (GPL), Open Source, and non profit software to explore scientific issues and applications of global computing and peer to peer distributed systems. For example, XtremWeb-HEP allows a high school, a university or a company to setup and run a global computing or peer to peer distributed system for either a specific application or a range of applications.