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Pseudonym Parties: An Offline Foundation for Online Accountability (PRELIMINARY DRAFT)

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Abstract

Many unsolved Internet security vulnerabilities reduce to a lack of user accountability: any user who misbehaves— e.g., by spamming from a free E-mail account or stuffing an online ballot box—can simply open other anonymous accounts or connect from other IP addresses. The obvious solution of requiring all users to identify and authenticat e themselves to online services, through a universal public- key infrastructure (PKI) for example, is inconvenient and impractical to deploy universally, and raises serious pri- vacy concerns. Ensuring accountability does not in gen- eral require identifying users, however: it only requires enforcing a principle of one person, one persona for a given online service. This paper proposes pseudonym par- ties, a decentralized scheme that combines technical tools (pseudonymous online accounts) with in-person social oc- casions (parties) to provide online accountability while preserving the ability of users to participate anonymously in online services. This approach is fully decentralized, can be deployed incrementally at minimal cost, and may even be fun to participate in.

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