Distributed File Systems
Eliezer Levy, Avi Silberschatz · 1989
Distributed File Systems are essential for sharing of data and storage space in a distributed system. A viewpoint that emphasizes the dispersed structure and decentralization of both data and control in the design of such systems is established. The concepts of location transparency, fault tolerance and scalability are defined and discussed in the context of Distributed File Systems. It is claimed that the principle of distributed operation is fundamental for a fault tolerant and scalable Distributed File System. Alternatives for the semantics of sharing and methods for providing access to remote files are also presented. A survey of current systems, namely Unix United, Locus, Sprite, Sun''s Network File System, and ITC''s Andrew, illustrates the discussed concepts and demonstrates various implementations and design alternatives. Based on the assessment of these systems, a point is made that a departure from the approach of extending centralized file systems over the network is necessary to accomplish sound Distributed File System design.