ZweiPhasenKommit

ZweiPhasenKommit, also known as Two-Phase Commit (2PC), is a protocol used in distributed computing to ensure that all participants in a distributed transaction agree on the outcome of the transaction. The protocol is designed to handle the coordination of distributed transactions, ensuring that either all participants commit their changes or none do, thus maintaining data consistency across the distributed system.

The Two-Phase Commit protocol operates in two main phases: the commit request phase and the commit phase. In the commit request phase, the coordinator, which is a designated node in the system, sends a request to all participants to prepare for the transaction. Each participant then performs the necessary checks and locks resources, but does not commit the transaction at this stage. If all participants can successfully prepare, the coordinator proceeds to the commit phase. In this phase, the coordinator sends a commit message to all participants, instructing them to commit the transaction. If any participant fails to prepare, the coordinator sends an abort message, and all participants roll back their changes.

The Two-Phase Commit protocol is widely used in database management systems and other distributed applications that require strong consistency guarantees. However, it has some limitations, such as the risk of a single point of failure at the coordinator and potential performance bottlenecks due to the synchronous nature of the protocol. Despite these limitations, Two-Phase Commit remains a fundamental technique for ensuring data consistency in distributed systems.