Abstract
The basic read/write shared memory model where asynchronous and crash prone processes communicate to solve a task is difficult to analyze. A more structured model is the iterated immediate snapshot model (IIS), where processes execute communication closed rounds. In each round, they communicate using read/write registers that cannot be reused in later rounds. It is known that a task is solvable in the IIS model if and only if it is solvable in the basic read/write model. Both models are also equivalent when, in addition to read/write registers, processes also have access to stronger communication objects called 01-tasks.
This paper extends further the task computability equivalence presenting a simulation that includes x-consensus objects, which solve consensus among up to x processes. The simulation implies that an iterated model where processes communicate through a sequence consisting only of x-consensus objects is equivalent to the basic shared memory model augmented with x-consensus objects.
S. Rajsbaum—Partially supported by a UNAM-PAPIIT grant.
D. Imbs and A. Valle—Part of this work was done while the authors were at the Instituto de Matemáticas, UNAM.
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Imbs, D., Rajsbaum, S., Valle, A. (2015). Untangling Partial Agreement: Iterated x-consensus Simulations. In: Pelc, A., Schwarzmann, A. (eds) Stabilization, Safety, and Security of Distributed Systems. SSS 2015. Lecture Notes in Computer Science(), vol 9212. Springer, Cham. https://doi.org/10.1007/978-3-319-21741-3_10
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