Open Grid Services Architecture And Application Development

Grid computing has emerged as an important new field of distributed computing with its goal to acquire convenient, flexible, secure, coordinated, standard and inexpensive resource sharing among distributed, inhomogeneous and dynamic collections of resources. A technical solution is required for grid resources' uniform accessing and seamless integration and this solution must be an international standard, so that all grid systems can be connected and interacted with each other. This standard must be an open standard, so that it can be extended conveniently and it must provide a specification to guide the implementation of the solution in detail. In addition, there must be an open resource toolkit which is comply to the standard and specification mentioned above for constructing diverse grid application systems by extending the core functions implemented by the toolkit.Open Grid Services Architecture (OGSA) provides a standard and solution to address these challenges. To implement the ideas and mechanisms presented by OGSA, Open Grid Service Infrastructure (OGSI) provides a software implementation model and specification of OGSA. Globus Toolkit 3 (GT3) is based on the core infrastructure compliant with OGSA, and it serves as a reference implementation of Open Grid Service Infrastructure (OGSI) and has been used by many large grid application projects.In this article, grid and grid computing is introduced at first; then OGSA, OGSI and GT3 are introduced and analysed detailedly; four base grid services systems are constructed based on GT3 to provide base capabilities for higher level grid applications; and a grid application--antispam grid system is designed and implemented at last.