Dfs vs. DFS

Have you wondered why Microsoft's distributed file system product is abbreviated and referenced as "Dfs" instead of "DFS"? Well, a product that owns the trademark designation for "DFS" is already on the market, and even more interesting, that product also provides distributed file system technology. The non-Microsoft DFS technology was developed years ago as part of the Open Software Foundation's (OSF's) distributed computing environment (DCE) specifications. As you may recall, OSF developed DCE to address interoperability between different UNIX operating systems, and between UNIX and non-UNIX operating systems. OSF later merged with X/Open to become The Open Group.

One of the many aspects of DCE is how file sharing occurs in a network environment. OSF originally considered Sun Microsystem's specification for the NFS, but it found NFS lacking in certain areas. OSF then looked at the Andrew File System (AFS), an NFS alternative developed at Carnegie Mellon University and commercialized by Transarc Corporation. To make a long story short, OSF found AFS lacking as well; OSF then worked with Transarc to define a follow-on specification to AFS called the Distributed File System (DFS).

DFS became part of the DCE specifications, but Transarc retained ownership of the name and the non-exclusive right to develop and market commercial DFS products. Transarc was so successful in developing and marketing its lines of AFS and DFS products that it attracted the attention of IBM, which acquired Transarc several years ago. Acquisition notwithstanding, Transarc continues to operate as an independent organization, and as it stands today, Transarc offers DFS products for both UNIX and NT environments.

So what relationship does Microsoft's Dfs have to DCE/Transarc's DFS? None. Zero. Zip. Zilch. Microsoft Dfs was not designed with the same goal in mind, and it does not interoperate with DFS. They are two totally different products that have very similar names.