Visible to the public PriFi: A Low-Latency and Tracking-Resistant Protocol for Local-Area Anonymous Communication

TitlePriFi: A Low-Latency and Tracking-Resistant Protocol for Local-Area Anonymous Communication
Publication TypeConference Paper
Year of Publication2016
AuthorsBarman, Ludovic, Zamani, Mahdi, Dacosta, Italo, Feigenbaum, Joan, Ford, Bryan, Hubaux, Jean-Pierre, Wolinsky, David
Conference NameProceedings of the 2016 ACM on Workshop on Privacy in the Electronic Society
PublisherACM
Conference LocationNew York, NY, USA
ISBN Number978-1-4503-4569-9
Keywordsanonymity, anonymity in wireless networks, anonymous communication, composability, controller area network security, dining cryptographers networks, Human Behavior, Local area networks, Metrics, pubcrawl, Resiliency, traffic analysis resistance
Abstract

Popular anonymity mechanisms such as Tor provide low communication latency but are vulnerable to traffic analysis attacks that can de-anonymize users. Moreover, known traffic-analysis-resistant techniques such as Dissent are impractical for use in latency-sensitive settings such as wireless networks. In this paper, we propose PriFi, a low-latency protocol for anonymous communication in local area networks that is provably secure against traffic analysis attacks. This allows members of an organization to access the Internet anonymously while they are on-site, via privacy-preserving WiFi networking, or off-site, via privacy-preserving virtual private networking (VPN). PriFi reduces communication latency using a client/relay/server architecture in which a set of servers computes cryptographic material in parallel with the clients to minimize unnecessary communication latency. We also propose a technique for protecting against equivocation attacks, with which a malicious relay might de-anonymize clients. This is achieved without adding extra latency by encrypting client messages based on the history of all messages they have received so far. As a result, any equivocation attempt makes the communication unintelligible, preserving clients' anonymity while holding the servers accountable.

URLhttp://doi.acm.org/10.1145/2994620.2994623
DOI10.1145/2994620.2994623
Citation Keybarman_prifi:_2016