The design of a secure distributed system

CHOTS stands for Corporate Headquarters Office Technology System and from the point of view of many of the users it is primarily an office automation system. CHOTS was, however, conceived as a secure infrastructure that supports communication betweeen users and both local and corporate applications and databases. The objective has been to give the user the same facilities that she would have in a large commercial organisation while at the same time protecting the data from unauthorised access by MOD staff as well as intruders. The author introduces the elements of secure distributed systems and how these are combined in a practical realisation based on the CHOTS experience