Blockchains and consensus protocols: Snake oil warning
Christian Cachin
EDCC 2017
This paper describes a Secure INtrusion-Tolerant Replication Architecture (SINTRA) for coordination in asynchronous networks subject to Byzantine faults. SINTRA supplies a number of group communication primitives, such as binary and multi-valued Byzantine agreement, reliable and consistent broadcast, and an atomic broadcast channel. Atomic broadcast immediately provides secure state-machine replication. The protocols are designed for an asynchronous wide-area network, such as the Internet, where messages may be delayed indefinitely, the servers do not have access to a common clock, and up to one third of the servers may fail in potentially malicious ways. Security is achieved through the use of threshold public-key cryptography, in particular through a cryptographic common coin based on the Diffie-Hellman problem that underlies the randomized protocols in SINTRA. The implementation of SINTRA in Java is described and timing measurements are given for a test-bed of servers distributed over three continents. They show that extensive use of public-key cryptography does not impose a large overhead for secure coordination in wide-area networks.
Christian Cachin
EDCC 2017
John J. Millson, Jonathan A. Poritz
Commun. Math. Phys.
Marcus Brandenburger, Christian Cachin, et al.
ACM TOPS
Alexander Shraer, Christian Cachin, et al.
CCS 2010