File Integrity in a Disc-Based Multi-Access System

  • A. G. Fraser


The operating system that is used on the Titan computer at Cambridge University includes procedures for the organization and maintenance of file storage. About 10,000 files, belonging to some 700 users, are held on a magnetic disc that has a total capacity of 128 million characters. For the past 4 1/2 years this system has been used on a scheduled 20-hour day to provide job-shop and multiple-access facilities to a total user population of about 1500 persons. The file management software is described here in some detail. An overview of the system will be found in reference [1], and further details will be found in references [2] and [3]. Under the heading of file management we include these procedures which are a concerned with file identification, file privacy, space allocation and file integrity. In this context a file may be any ordered string of data and it is of no interest to the file management software to know what that data represents. In practice each file is held as a string of blocks (one block can accommodate 4096 characters). A quite distinct set of data handling routines provide the user with convenient means of processing the contents of a file. The file management software consists of complete programs that operate under supervisor control in the manner normally associated with other users of the system.


Magnetic Tape Directory Entry Archive File File Management File Directory 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Barron et al„ “File Handling at Cambridge University”. AFIPS Conf: Proc. 30 (SJCC 1967), 163.Google Scholar
  2. 2.
    “An introduction to the Cambridge multiple-access system”. University Mathematical Laboratory, Cambridge (1968).Google Scholar
  3. 3.
    “Cambridge multiaccess system manual”. University Mathematical Laboratory, Cambridge (1968).Google Scholar

Copyright information

© Springer Science+Business Media New York 2001

Authors and Affiliations

  • A. G. Fraser

There are no affiliations available

Personalised recommendations