OGSA(Open Grid Services Architecture) is called the next generation grid architecture. It evolves from theearly five levels hourglass model architecture. OGSA consists of two key technologies: grid technology and Web Ser-vice technology. OGSA gives emphasis to services and all things in OGSA are services. After explaining the basic ideaof OGSA,this paper introduces the composition of OGSA-based hosting environment and virtual organization. Todemonstrate the process of how an application is executed in an OGSA-based environment,the paper gives an exampleof data mining which illustrates the basic functions and working mechanism of OGSA. A brief comparison to relatedgrid architecture is also given in the paper. The paper concludes that OGSA is not mature and it needs improvementtogether with related technology and grid applications.
