DFS

Developed by:
Xerox Corporation, Palo Alto Research Center, USA H. Sturgles, J. Mitchell and J. Israel

Short Description:
The distributed file system (DFS) is implemented to provide a transparent file handling mechanism so that any authorized user can access any file in the network by simply mentioning the name without knowing the physical location. To retrieve data the user submits a query which the DFS broadcasts to all the nodes where the query is executed. The results are then transmitted back to the originating node, where they are compiled and displayed to the user. The DFS is designed after considering the various req uirements and specifications peculiar to the defence environment. In view of the hierarchic organizational structure of the defence services, a distributed data storage system was envisaged in which skeleton files with the same record structure are automa tically generated at all available lateral nodes, whenever the new file is created at any node, i.e. the data is partitioned horizontally. The distributed file system described differs from existing file servers, namely Cambridge File Server, Felix File S erver, Sanchay, etc., in the important aspect that whereas all the above systems provide primitive facilities at the file and page level, the presented system provides additional facilities for automatic update of files after validation and a network tran sparent query facility.

Model: server/client
Properties: atomic transactions
Transparency: access, location, replication
Running on:
Date: 1980

References:
H. Sturgles, J. Mitchell and J. Israel: "Issues in the Design and Use of Distributed File System". ACM Operating Systems Review, July 1980.

A. Jain, H. N. Mahabala, K. B. Lakshmanan and S. Srinivasan: "A distributed file system with query processing facility over PRIMENET". Madras, India 19-2 Comput. Soc. India, IFIP, UNESCO, NETWORKS India 84. International Symposium on Data Communication an d Computer Networks, 19-21 Oct. 1984, pp.196-197, 6 REFS. Treatment PRACTICAL.