PhD Seminar • Cryptography, Security, and Privacy (CrySP) • Peer2PIR: Private Queries for IPFS

Friday, April 12, 2024 2:00 pm - 3:00 pm EDT (GMT -04:00)

Please note: This PhD seminar will take place online.

Miti Mazmudar, PhD candidate
David R. Cheriton School of Computer Science

Supervisor: Professor Ian Goldberg

The InterPlanetary File System (IPFS) is a peer-to-peer network for storing data in a distributed file system. Despite its prominence, the privacy properties that IPFS offers to peers are severely limited. Any query within the network leaks to other peers the content for which a peer is querying. Amending the existing privacy problem within IPFS would incentivize greater usage of the system and prevent further attacks.

In this talk, I will present our work, Peer2PIR, which addresses the privacy leakage across three functionalities, namely peer routing, provider advertisements, and content retrieval. Ultimately, Peer2PIR empowers peers to privately navigate and retrieve content within IPFS. I will argue that private information retrieval (PIR) is the most suitable tool for our task. I will also highlight and address novel challenges inherent to integrating PIR into distributed systems. I will present our new, private algorithms for each of the three functionalities, and demonstrate that they incur minimal overheads. I will also include a systematic comparison of state-of-art PIR protocols in the context of distributed systems which may be of independent interest. I will conclude with privacy engineering takeaways based on our work.