  This paper describes BlockPKI, a blockchain-based public-key infrastructure
that enables an automated, resilient, and transparent issuance of digital
certificates. Our goal is to address several shortcomings of the current TLS
infrastructure and its proposed extensions. In particular, we aim at reducing
the power of individual certification authorities and make their actions
publicly visible and accountable, without introducing yet another trusted third
party. To demonstrate the benefits and practicality of our system, we present
evaluation results and describe our prototype implementation.
