The Software Upgrade Protocol (or SUP) System is a set of programs developed by Carnegie Mellon University

Carnegie Mellon University

Carnegie Mellon University is a private research university in Pittsburgh, Pennsylvania, United States....

 in the 1980s (as was the Andrew File System

Andrew file system

The Andrew File System is a distributed networked file system which uses a set of trusted servers to present a homogeneous, location-transparent file name space to all the client workstations. It was developed by Carnegie Mellon University as part of the Andrew Project. It is named after Andrew...

). It provides for collections of files to be maintained in identical versions across a number of machines.

It was originally developed under the Mach

Mach (kernel)

Mach is an operating system kernel developed at Carnegie Mellon University to support operating system research, primarily distributed and parallel computation. Although Mach is often mentioned as one of the earliest examples of a microkernel, not all versions of Mach are microkernels...

operating system, but implementations are provided with Debian & Ubuntu Linux distributions.