Two Phase Commit Protocol for Distributed Communication Systems
Original Publication Date: 1981-Jul-01
Included in the Prior Art Database: 2005-Feb-11
This invention relates to a method for execution of a two-phase COMMIT/ABORT operation in a DEMAND/RESPONSE protocol among communicating nodes in a network in an environment of node failures and lost messages. The method steps result in 2N handshakes per message transfer per node, whereas the prior art, as applied to centralized protocols, has required 3N handshakes per message transfer per node. The method steps comprise the transmission of an intent message to each node in sequence as a condition precedent to the sending of a COMMIT message. Each node must record its prepared state on stable storage and set a timer to guard against lost COMMIT messages. Any negative acknowledgment results in the transmission of an ABORT message and an ABORT acknowledgment.