Marten van Dijk and co-authors win ACM CCS 2023 Test of Time Award

Data encryption alone is often not enough to protect users’ privacy in outsourced storage applications. The sequence of storage locations accessed by the client (the access pattern) can leak a significant amount of sensitive information about the unencrypted data through statistical inference. For example, it was demonstrated by others that by observing accesses to an encrypted email repository, an adversary can infer as much as 80% of the search queries.

Oblivious RAM (ORAM) algorithms, first proposed by Goldreich and Ostrovsky, allow a client to conceal this access pattern to the remote storage by continuously shuffling and re-encrypting data as they are accessed. An adversary can then observe the physical storage locations accessed, but the ORAM algorithm ensures that this adversary has negligible probability of learning anything about the true (logical) access pattern.

Since its proposal, the research community has strived to find an ORAM scheme that is also practical. In the now winning paper, the authors proposed a novel ORAM algorithm, which was at the time the most practical ORAM construction under small client storage. They proved theoretical bounds on its performance and also presented matching experimental results. The core of their construction is called Path ORAM because data on the server is always accessed in the form of tree paths.

Van Dijk heads the Computer Security research group at CWI, the national research institute for mathematics and computer science in the Netherlands, and is a professor at VU Amsterdam. He has more than 20 years of research experience in secure computation. He acquired this experience both in academia (MIT and the University of Connecticut in the USA) and in industry (Philips Research and RSA Laboratories). He received the A. Richard Newton Technical Impact Award in Electronic Design Automation in 2015 and the Most Frequently Cited Paper Award (2000-2009), Symposium on VLSI Circuits, for his collaboration on Physical Unclonable Functions.

Aegis, the first single-chip secure processor that encrypts and verifies the integrity of external memory and introduced the concept of secure containers, got a Test of Time Award from Intel in 2022. This concept is in widespread use in Trusted Execution Environments, such as the Intel SGX processor in industry.

The RAM protocol ‘Path ORAM’ received a best paper award at CCS 2013, was selected as a 2018 Top Pick in Hardware and Embedded Security and just received the ACM CCS 2023: Test of Time Award. Van Dijk further won the 2023 IEEE CS Edward J. McCluskey Technical Achievement Award.

Marten van Dijk is an IEEE Fellow for his contributions to secure processor design and encrypted calculations. He is also a member of the advisory council of ACCSS, the association of all scientists working in cybersecurity in the Netherlands and chair of the Special Interest Group Cyber Security (SIG-CS) of ICT Research Platform Nederland (IPN).