WSRF melds grid computing and Web services

Two key computing initiatives are set to merge. The Global Grid Forum, the entity that creates grid computing specifications, recently decided to re-engineer grid computing standards, merging them with the most current Web services standards.

Furthermore, the new specification, called Web Services Resource Framework (WSRF), has been submitted to OASIS, the Web services standards body, bringing the GGF and OASIS into closer collaboration.

WSRF will also be adopted by the Globus Alliance’s grid computing tool kit, the Globus Toolkit 4.0 (GT4), which is expected by early 2005. This is great news for both grid and Web services development communities because WSRF will be jointly developed, creating a common infrastructure and giving the two communities new common standards, skills and tools.

Today’s grid computing implementations are usually based on the Open Grid Services Infrastructure (OGSI) specification. Based on XML Schema Definitions and WSDL, OGSI provides useful tools for Web services developers. OGSI, however, was based on older Web services specifications and has become cumbersome for developers accustomed to the newer Web services specifications. “OGSI took a very aggressive approach to WSDL and schemas, which put a lot of stress on people trying to use it,” says David Snelling, chair of the new OASIS WSRF technical committee and active member of the GGF.

WSRF embodies a major advance over both OGSI and existing Web services specifications in that it supports stateful Web service interfaces.

OGSI includes “hooks” for addressing stateful resources, since in grid computing each node has an associated state. Yet most Web services interfaces are stateless.

WSRF defines a new approach for accessing stateful resources which supports the grid computing infrastructure and also provides for stateful Web services in general – in other words, the special-case solution for grid computing (in OGSI) was generalized to the benefit of all Web services (through WSRF). The jointly developed WSRF specification reflects a strong positive collaboration between GGF and OASIS. The two organizations have been producing joint work at the grass-roots level for more than a year now, Snelling says.

WSRF was submitted as a draft specification to the OASIS organization in March, and the technical committee convened for the first time April 28.

Support for WSRF will be available in the next generation of the Globus Toolkit, GT 4, as noted, which is due out early next year and will implement the full WSRF specification and comply with the latest Web services specifications.

Grid computing users are excited by the development, which represents further convergence in the infrastructure of grid computing and Web services, bringing the two communities closer together and spurring development of other shared tools and standards. “We will be playing with the early release code all through the summer,” says a senior architect for one of the largest active grid computing implementations, who is planning to implement WSRF as soon as it’s released.