A Flexible Security System for Metacomputing Environments

. A metacomputing environment is a collection of geographically distributed resources (people, computers, devices, databases) connected by one or more high-speed networks, and potentially spanning multiple administrative domains. Security is an essential part of metasystem design---high-level resources and services defined by the metacomputer must be protected from one another and from corrupted underlying resources, and underlying resources must minimize their vulnerability to attacks from the metacomputer level. We present the Legion security architecture, a flexible, adaptable framework for solving the metacomputing security problem. We demonstrate that this framework is sufficiently flexible to implement a wide range of security mechanisms and high-level policies. 1 Introduction Legion [5, 6] is a distributed computing platform for combining very large collections of independently administered machines into single, coherent environments. Like a traditional operating system, Legion..