The relevance of employing the IDS intrusion detection mechanism in a clustered wireless sensor network (WSN) in order to withstand attacks performed by the intruder introducing an illegitimate sensor node is displayed. This node taking on cluster head node functions leads to increasing information security risks for the whole cluster zone of the WSN. A description of the anomaly-based intrusion detection system (IDS) suggested is provided. Both physical and data link layers of a cluster zone sensor node are considered.