AFS (originally Andrew File System)
is a distributed file and authentication service designed to be scaleable to
many client computers, using secure authentication and with flexible access control.
The main features are:
Server functions can be distributed across multiple servers to spread load, add
redundancy and fault tolerance. This includes authentication and protection databases
in addition to file data. A collection of servers comprises a cell.
Data may be moved between servers while active, and transparently to the end users.
Servers may be brought on- and off-line while the system is active.
Almost all administrative functions can be performed from any client.
Scales well to many clients.
All clients get an identical view of the entire cell.
Flexible access controls; by user, group (user-managed) or machine (IP).
Can replicate read-only volumes for redundancy
Uses kerberos authentication to identify users and grant access to files. Client
computers are not trusted.
Authentication process always encrypted. File contents optionally encrypted in transit.
Client software is available for almost all Unix platforms, including Linux and Mac OS-X,
plus Microsoft Windows (2000 and later).
Gateways to NFS, Windows 9x and Mac classic are available.
Cross-cell operation is possible. AFS is a global filesystem.
Developed by CMU, commercialized by Transarc, bought by IBM, branched into DFS/DCE, made open source
(OpenAFS.org).