The Chinese Wall security policy

The authors explore a commercial security policy (the Chinese Wall) which represents the behavior required of those persons who perform corporate analysis for financial institutions. It can be distinguished from Bell-LaPadula-like policies by the way that a user's permitted accesses are constrained by the history of his previous accesses. It is shown that the formal representation of the policy correctly permits a market analyst to talk to any corporation which does not create a conflict of interest with previous assignments. The Chinese Wall policy combines commercial discretion with legally enforceable mandatory controls. It is required in the operation of many financial services organizations; the authors conclude that it is, therefore, perhaps as significant to the financial world as Bell-LaPadula's policies are to the military.>