The fast expansion of Grid technologies emphasizes the importance of network performance measurement. Some network measurement methods, like TCP throughput or latency evaluation, are very sensitive to concurrent measurements that may devalue the results. This paper presents the Probes Coordination Protocol (PCP) which can be used to schedule different network monitoring tasks. In addition, this paper goes on to discuss the main properties of the protocol; these being, flexibility, efficiency, robustness, scalability and security. This study presents the results of its evaluation and of experiment periodicity measurements.