As part of the formation of OSF, various members contributed many of their ongoing research projects. At the time, network computing was quite popular, and many of the companies involved were working on similar RPC-based systems. By re-building these various utilities on a single "official" RPC mechanism, OSF could offer a major advantage over SVR4, allowing any DCE-supporting system (namely OSF/1) to interoperate in a larger network.
The DCE system was, to a large degree, based on independent developments made by each of the partners. DCE/RPC was derived from the Network Computing System (NCS) created at Apollo Computer. The naming service was derived from work done at Digital. DCE/DFS was based on the Andrew File System (AFS) originally developed at Carnegie Mellon University. The authentication system was based on Kerberos, and the authorization system based on Access Control Lists (ACLs). By combining these features, DCE offers a fairly complete C-based system for network computing. Any machine on the network can authenticate its users, gain access to resources, and then call them remotely using a single integrated API.
Distributed computing never really caught on as much as had been hoped for in the late 1980s and early 1990s. The rise of the Internet, Java and web services stole much of its mindshare through the mid-to-late 1990s, and competing systems such as CORBA muddied the waters as well. Perhaps ironically, one of the major uses of DCE/RPC today are Microsoft's DCOM and ODBC systems, which use DCE/RPC (in MSRPC) as their network transport layer.
OSF and its projects eventually became part of The Open Group, which released DCE 1.2.2 under a free software license (the LGPL) on 12 January 2005. DCE 1.1 was available much earlier under the OSF BSD license, and resulted in FreeDCE being available since 2000. FreeDCE contains an implementation of DCOM.
Major components of DCE within every cell are:
Modern DCE implementations such as IBM's are fully capable of interoperating with Kerberos as the security server, LDAP for the CDS and the Network Time Protocol implementations for the time server.
While it is possible to implement a distributed file system using the DCE underpinnings by adding filenames to the CDS and defining the appropriate ACLs on them, this is not user-friendly. DCE/DFS is a DCE based application which provides a distributed filesystem on DCE. DCE/DFS can support replicas of a fileset (the DCE/DFS equivalent of a filesystem) on multiple DFS servers - there is one read-write copy and zero or more read only copies. Replication is supported between the read-write and the read-only copies. In addition, DCE/DFS also supports what are called "backup" filesets, which if defined for a fileset are capable of storing a version of the fileset as it was prior to the last replication.
DCE/DFS is believed to be the world's only distributed filesystem that correctly implements the full POSIX filesystem semantics, including byte range locking. DCE/DFS was sufficiently reliable and stable to be utilised by IBM to run the back-end filesystem for the 1996 Olympics web site, seamlessly and automatically distributed and edited worldwide in different timezones.
US Patent Issued to International Business Machines on March 29 for "Distributed Filesystem Network Security Extension" (Texas Inventors)
Mar 30, 2011; ALEXANDRIA, Va., March 30 -- United States Patent no. 7,917,751, issued on March 29, was assigned to International Business...