We present the first optimally resilient, bounded, wait-free implementation of a distributed atomic register, tolerating Byzantine readers and (up to one-third of) Byzantine servers, without the use of unproven cryptographic primitives or requiring communication among servers. Unlike previous (non-optimal) solutions, the sizes of messages sent to writers depend only on the actual number of active readers and not on the total number of readers in the system. With a novel use of secret sharing techniques combined with write back throttling we present the first solution to tolerate Byzantine readers information theoretically, without the use of cryptographic techniques based on unproven numbertheoretic assumptions.
Amitanand S. Aiyer, Lorenzo Alvisi, Rida A. Bazzi