ylfink@water.waterloo.edu (ylfink) (09/20/88)
DEPARTMENT OF COMPUTER SCIENCE UNIVERSITY OF WATERLOO SEMINAR ACTIVITIES SYSTEMS SEMINAR - Tuesday, September 27, 1988 Professor John Dobson, Computing Laboratory, University of Newcastle upon Tyne, U.K., will speak on ``Security Modelling for Information Technology Systems''. TIME: 3:30 PM ROOM: DC 1304 ABSTRACT Arguments will be presented that suggest the traditional approach for modelling security, based on information flow, is ill-founded; work at Newcastle is underway on finding a more appropriate model based on ways of modelling the enterprise whose needs the secure system is intended to serve. The two key ideas behind this modelling technique are the notion of dependability, defined as that property of a computing system which allows reliance justifiably to be placed on the service which it delivers; and the idea that this definition can be interpreted only by understanding the roles, rights and responsibilities of those who are relying on the system in the context of the organisation as a whole, which is of course subject to its own set of policies and constraints (which have to be formally expressed). The talk will describe how an organisation is modelled, and how this naturally leads to modelling the security policies which have to be obeyed by a computer system within the organisation.