Using extended hierarchical quorum consensus to control replicated data: from traditional voting to logical structures

We present a new replica control protocol that logically imposes a hierarchy onto the set of copies and introduces the blind-write as another operation (besides the traditional read and write) defined over the replicated data. With this third operation, and by deriving quorums from the hierarchy in a different way, the proposed protocol turns out to be a generalization of the traditional voting scheme and other existing replica control protocols based on symmetrical logical structures like grids or hierarchies. Compared to these protocols, the proposed protocol also improves the system response time by achieving better ratios between quorums size and the total number of copies, even under high availability requirements.<>