# Wait-free approximate agreement on graphs

@inproceedings{Alistarh2021WaitfreeAA, title={Wait-free approximate agreement on graphs}, author={Dan Alistarh and Faith Ellen and Joel Rybicki}, booktitle={SIROCCO}, year={2021} }

Approximate agreement is one of the few variants of consensus that can be solved in a wait-free manner in asynchronous systems where processes communicate by reading and writing to shared memory. In this work, we consider a natural generalisation of approximate agreement on arbitrary undirected connected graphs. Each process is given a vertex of the graph as input and, if non-faulty, must output a vertex such that – all the outputs are within distance 1 of one another, and – each output value…

## 3 Citations

Brief Announcement: Variants of Approximate Agreement on Graphs and Simplicial Complexes

- Computer SciencePODC
- 2021

This work shows that both tasks of approximate agreement on graphs, edge agreement and clique agreement arise as special cases of a more general, higher-dimensional, approximate agreement task, where the processes must agree on the vertices of a simplex in a given simplicial complex.

Reductions and Extension-Based Proofs

- Computer SciencePODC
- 2021

It is proved that, if T reduces to S, and T has an augmented extension-based proof that it is impossible to solve in the NIS model, then so does S.

Why extension-based proofs fail

- Computer ScienceSTOC
- 2019

This work introduces extension-based proofs, a class of impossibility proofs that are modelled as an interaction between a prover and a protocol and that include valency arguments.

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