Design and Implementation of an Intrusion-Tolerant Tuple Space

The tuple space coordination model is one of the most interest-ing communication models for open distributed systems due to its space and time decoupling and its synchronization power. Sev-eral works have tried to improve the dependability of tuple spaces. Some have made tuple spaces fault-tolerant while others have fo-cused on security. However, many practical applications in the Internet require both these dimensions. This paper describes the design and implementation of DEPSPACE, a dependable communi-cation infrastructure based on the tuple space coordination model. DEPSPACE is dependable in a strong sense of the word: it is secure, fault-tolerant and intrusion-tolerant, i.e. it behaves as expected even if some of the machines that implement it are successfully attacked. Moreover, it is a policy-enforced augmented tuple space, a shared memory object that we have recently proven to be universal, i.e., capable of implementing any other shared memory object