Wait-free approximate agreement on graphs

  title={Wait-free approximate agreement on graphs},
  author={Dan Alistarh and Faith Ellen and Joel Rybicki},
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… 

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