1. A Comparison of Commercial and Military Computer Security Presenter: Ivy Jiang1 A Comparison of Commercial and Military Computer Security Policies Authors: D. Clark & D. Wilson IEEE Symposium on Security and Privacy, pp.184-194, IEEE,1987 “Any discussion of mechanisms to enforce computer security must involve a particular security policy that specifies the security goals the system must meet and the threats it must resist.” Presenter: Ivy Jiang

2. A Comparison of Commercial and Military Computer Security Presenter: Ivy Jiang2 About the Paper Military Security Policy defined by the Department of Defense Trusted Computer System Evaluation Criteria (the “Orange Book”)  Goal: classified information must not be disclosed to unauthorized individuals  Mechanism: Discretionary Control & Mandatory Controls Security Policy valid in Commercial Situation  Goal: ensure integrity of data to prevent fraud and errors  Mechanism: Well-formed Transaction & Separation of Duty Military VS Commercial  “There is a clear difference of emphasis in the military and commercial worlds”  Distinct mechanisms are required for enforcement of security policies in commercial system

3. A Comparison of Commercial and Military Computer Security Presenter: Ivy Jiang3 Compare to the Military Mechanism In the Commercial Mechanism Data item is not necessary associated with a particular security level Data item is manipulated by a restricted set of programs and programs must meet well formed transaction rules User is not given authority to read/write data User is given authority to execute certain program and this authority must meet separation of duty rules

4. A Comparison of Commercial and Military Computer Security Presenter: Ivy Jiang4 Appreciative Comment Provide statement to support that “Distinct mechanisms are required for enforcement of security policies in commercial system”  “Several security systems used in the commercial environment…...evaluated using the Orange Book……..they did not meet the mandatory requirements of the security model as described in the Orange Book”  “These packages are used commonly in industry and viewed as being rather effective in their meeting of industry requirement

5. A Comparison of Commercial and Military Computer Security Presenter: Ivy Jiang5 Critical Comment - #1 What is “lattice model”?  “We argue that a lattice model is not sufficient to characterize integrity policies”  Lattice model ?= mandatory control

6. A Comparison of Commercial and Military Computer Security Presenter: Ivy Jiang6 Critical Comment - #2 Is there overlap between two mechanisms?  “ There is not effective overlap between the mechanisms for the two”  “Incorporation of some form of integrity controls into the Orange Book might lead to systems that better meet the needs of both group”

7. A Comparison of Commercial and Military Computer Security Presenter: Ivy Jiang7 Question What is the proper emphasis of a security policy in the Military world? (Confidentiality, Integrity, Availability?)