Reaching approximate agreement in the presence of faults
Journal of the ACM (JACM)
ACM Transactions on Programming Languages and Systems (TOPLAS)
On the robustness of Herlihy's hierarchy
PODC '93 Proceedings of the twelfth annual ACM symposium on Principles of distributed computing
A completeness theorem for a class of synchronization objects
PODC '93 Proceedings of the twelfth annual ACM symposium on Principles of distributed computing
Consensus power makes (some) sense! (extended abstract)
PODC '94 Proceedings of the thirteenth annual ACM symposium on Principles of distributed computing
Impossibility of distributed consensus with one faulty process
Journal of the ACM (JACM)
Failure detectors and the wait-free hierarchy (extended abstract)
Proceedings of the fourteenth annual ACM symposium on Principles of distributed computing
The topological structure of asynchronous computability
Journal of the ACM (JACM)
The consensus power of shared-memory distributed systems
The consensus power of shared-memory distributed systems
Distributed Computing: Fundamentals, Simulations and Advanced Topics
Distributed Computing: Fundamentals, Simulations and Advanced Topics
On asymmetric progress conditions
Proceedings of the 29th ACM SIGACT-SIGOPS symposium on Principles of distributed computing
Renaming is weaker than set agreement but for perfect renaming: a map of sub-consensus tasks
LATIN'12 Proceedings of the 10th Latin American international conference on Theoretical Informatics
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Objects like queue, swap, and test-and-set allow two processes to reach consensus, and are consequently "universal" for a system of two processes. But are there deterministic objects that do not solve 2-process consensus, and nevertheless allow two processes to solve a task that is not otherwise wait-free solvable in read-write shared memory? The answer "no" is a simple corollary of the main result of this paper: Let A be a deterministic object such that no protocol solves consensus among n+1 processes using copies of A and read-write registers. If a task T is wait-free solvable by n + 1 processes using read-write shared-memory and copies of A, then T is also wait-free solvable when copies of A are replaced with n-consensus objects. Thus, from the task-solvability perspective, n-consensus is the second strongest object (after (n+1)-consensus) in deterministic shared memory systems of n+1 processes, i.e., there is a distinct gap between n- and (n + 1)-consens. We derive this result by showing that any (n+1)-process protocol P that uses objects A can be emulated using only n-consensus objects. The resulting emulation is non-blocking and relies on an a priori knowledge of P. The emulation technique is another important contribution of this paper.