A new IDS system, Jev-IDS, is proposed based on the Jev System One Model (SOM) for network intrusion detection. It uses a Large Language Model (LLM) to analyze flow records directly, offering faster and cheaper detection with higher recall compared to traditional machine-learning-based IDS. The system asks the LLM two questions per flow and achieves an F1-score of 0.859 on a 300-flow pilot test.