Integrated Platforms and Toolkits -- these systems provide uniform access to heterogeneous resources across wide area networks. Traditionally, their focus has been on High Performance Computing environments.
- AVAKI -- commercial software providing both data grid and compute grid functionality.
- Globus -- viewed by many as the de facto standard, this is an open source initiative to develop grid technologies. Also supported commercially with Platform Globus and the IBM Grid Toolbox. IBM has also published a Red Book on implementing Globus.
- Legion -- developed at the University of Virginia, this is the project that spawned AVAKI; since that time, the two have diverged significantly.
- MyGrid -- developed at the University of Manchester in the UK aimed at producing a virtual laboratory workbench that will serve the life sciences community.
- NSF Middleware Initiative (NMI) -- at its core, NMI is another Globus distribution, but they also include a number of other key components such as Condor-G, Network Weather Service, KX.509/KCA (Kerberos-enabled X.509), and GSI-enabled OpenSSH.
- Open Grid Services Architecture (OGSA) -- chartered by the Global Grid Forum, this is the effort that is building a standards-based grid architecture, parts of which resemble or extend web services.
- UNICORE -- developed in support of the EUROGRID project.
PC Aggregation -- these grid systems are designed primarily to aggregate cycles on low-end desktop PC's across local and wide area networks.