Propose Phase Sample Clauses

Propose Phase. Any leader executing the Propose phase of a round has previously executed the cor- responding Prepare phase. During the following Propose phase, a Write operation exe- cuted by the leader aims at suggesting a safe value to the acceptors. If enough acceptors follow this suggestion, this value becomes the decision value. The leader broadcasts a Write request (also called a ▇▇▇▇▇ ▇▇ request) to all acceptors. This request carries the previously selected value and the round number. Once it receives such a message, an acceptor adopts the value of the leader only if it still takes part to the round number contained in the request or to a lower round number. If another leader has acted with a higher round number, the acceptor has proceeded to another round and will ignore the request of the leader. In order to complete the Propose phase, a leader must gather replies from a majority quorum of acceptors. These replies, also called Phase 2b mes- sages, inform the leader that a majority of acceptors have adopted the value suggested by the leader. In this case, the leader can safely decide the value. Figure 3.3 emphasizes the steps of the Propose phase.