Perhaps the most common parellel drawn is between summit and NFS, the Network File System. NFS is a system that was built to share files with many users and potentially disconnected systems. This is a feature that summit also offers. There are a few important differences, however. For one, NFS is not inherently secure. Securing your NFS data requires extra setup. Also Exporting filesystems to remote systems requires setting up more software and more admininistration. Summit gives you all of this out of the box--security, easy exporting of data and remote administration.

More important than the feature differences between NFS and summit, however, is the fact that all NFS does is serve files. It doesn't set up any mechanisms for communication, process support, memory etc. In order to use any of these along with file sharing, you need to set up ther systems, and somehow get them to communicate with your NFS system. Summit has all of these built into one system. It also allows you to share multiple filesystems from any platform that supports summit to any platform that supports summit. Again, keep in mind that the goal of summit is to provide a fundimentally open system that lets you treat any systems as one, homogeneous system. Certainly you could duplicate some of summit's functionality using NFS, but not all of it, and not with the same flexability and cross-platform ease.

Another similar system is DCE, the Distributed Computing Environment. It is a way of (unsurprisingly) building distributed programs. It uses an RPC (remote procedure calling) mechanism. It is a standard, and there are many UNIX systems that can use it. Again, much of the functionality in summit can be replicated in DCE, and in fact there are things that you can do with DCE that aren't available in summit. Again, however, it's important to keep these systems in context.

DCE is not built to take advantage of shared files. It can't talk with something like NFS, so if there are files that are unavailable where part of a program is running, there is no way to access these files. It also isn't built to be able to communicate with any systems other than UNIX systems, and the setup and administration overhead is enormous. Summit provides the file access, cross-platform distribution and ease of setup. Hopefully future versions of summit would prvide a simple RPC mechanism, so that most of DCE's features would be availabe in summit. The imporant issue here is, again, that while there is another program that gives you some of summit, DCE is not built to be an open system. It does not use known protocols that can connect disperate systems.