Which security tool is effective for monitoring network traffic and detecting intrusions?

The choice of Wireshark as an effective security tool for monitoring network traffic and detecting intrusions is grounded in its capability to analyze the packets of data flowing across the network. Wireshark is a powerful network protocol analyzer that allows security professionals to capture and inspect data in real-time or from previously recorded sessions.

This tool provides detailed insights into the traffic, enabling users to dissect the information carried in each packet. By examining these packets, analysts can identify unusual patterns or anomalies that may indicate unauthorized access or malicious activities. Wireshark also facilitates the examination of various protocols, making it highly versatile for understanding network behavior and detecting potential intrusions.

While other options may serve important roles in network security—such as intrusion prevention systems that actively block detected threats, firewalls that filter traffic based on predefined rules, and spam filters that primarily target unsolicited emails—they do not function primarily as tools for in-depth packet analysis and traffic monitoring like Wireshark. Thus, Wireshark's specific focus on detailed traffic examination makes it the most appropriate choice for the task of detecting intrusions through traffic monitoring.