arXiv subjects
Publications and source records attributed to Aljoscha Meyer.
We present new schemes for solving prefix authentication and secure relative timestamping. By casting a new light on antimonotone linking schemes, we improve upon the state of the art in prefix authentication, and in timestamping with rounds of bounded length. Our designs can serve as more efficient alternatives to certificate transparency logs.
Secure relative timestamping and secure append-only logs are two historically mostly independent lines of research, which we show to be sides of the same coin -- the authentication of prefix relations. From this more general viewpoint, we derive several complexity criteria not yet considered in previous literature. We define transitive prefix authentication graphs, a graph class that captures all hash-based timestamping and log designs we know of. We survey existing schemes by expressing them as transitive prefix authentication graphs, which yields more compact definitions and more complete evaluations than in the existing literature.
Range-based set reconciliation is a simple approach to efficiently computing the union of two sets over a network, based on recursively partitioning the sets and comparing fingerprints of the partitions to probabilistically detect whether a partition requires further work. Whereas prior presentations of this approach focus on specific fingerprinting schemes for specific use-cases, we give a more generic description and analysis in the broader context of set reconciliation. Precisely capturing the design space for fingerprinting schemes allows us to survey for cryptographically secure schemes. Furthermore, we reduce the time complexity of local computations by a logarithmic factor compared to previous publications.