The COllaborative Redundant Processing (CORP) algorithm is an approach to prevent unauthorised modification of data in a decentralised and distributed computing environment. Built on Ki-Nga-Kopuku, a distributed and decentralised security model for Cloud Computing, where redundant nodes are functionally identical, the nodes collectively maintain consistency and integrity of processed data. If a single node is compromised and acts maliciously to modify data, other nodes detect the action. CORP extends the functionality of Ki-Nga-Kopuku and is developed mainly for a Cloud Computing context, but the concept can be used in any distributed and decentralised environment to provide consistency, integrity, and availability.