Decentralized Management of Security in Distributed Systems

Autonomy implies that each component system should have the ability to specify the security policy with respect to resources that it controls. The composition of these multiple security policies into a coherent system-wide policy is a major challenge in the management of distributed systems. Autonomy also implies that the security o cer of each component system has discretion regarding the trust invested in other component systems. The individual security o cers of component systems should be free within speci ed parameters to con gure the security policy of their system and its interactions with other components. At the same time it should be possible to analyze the net global result of these individual decisions. Analyzing the composition and interaction of security policies is therefore extremely important in a distributed environment with multiple autonomous points of security control.