Intrusion tolerance, or the ability to operate correctly even while partially compromised by an attacker, is an increasingly important concern for high value systems. However, despite a long line of work on using Byzantine Fault Tolerant (BFT) replication to enable such high value systems to withstand successful intrusions, such solutions are still challenging to deploy in practice and require a high level of expertise to manage.
Further complicating deployment, we have shown that tolerating sophisticated network attacks in addition to intrusions requires that system management and state be distributed across at least three distinct geographic sites (see “Network-Attack-Resilient Intrusion-Tolerant SCADA for the Power Grid”).
We are developing new techniques to make intrusion-tolerant systems easier to deploy by offloading part of the system management to a cloud service provider. However, this raises significant confidentiality concerns, as sharing sensitive data and/or proprietary algorithms with a cloud provider may not be an acceptable trade-off.
Our recent work, “Toward Intrusion Tolerance as a Service: Confidentiality in Partially Cloud-Based BFT Systems”, published in DSN 2021 has shown how we can make use of cloud sites to host additional system replicas without needing to expose any unencrypted state to the cloud.
We are continuing to work to develop new architectures to further simplify system management and meet the needs of a broad range of applications.