An algorithm for mutual exclusion of simultaneous access of different processes to the same object in dynamic P2P systems is proposed, aimed at reducing service traffic. The main idea of it is the transmission of messages between the request nodes and the coordinator. The information of n duplicates of the Co object is published in t nodes (in the coordinator and his candidates). Nodes send a request to the coordinator of duplicate owners to gain access to the object. The paper describes the relevance and essence of the algorithm, experimentally, by imitation, its scalability and efficiency are evaluated.