Cisco Cyber Security Practice Exam

What system analyzes a copy of network traffic rather than the actual forwarded packets?

1. IPS

2. Firewall

3. IDS

4. Switch

The correct answer is: IDS

In the context of network security, an Intrusion Detection System (IDS) is specifically designed to analyze a copy of the network traffic instead of inspecting and altering the actual packets that are forwarded across the network. The primary function of an IDS is to monitor and analyze network or system activities for malicious activities or policy violations, by reviewing a duplicated stream of network data. An IDS operates in a passive manner, often receiving its data from a network tap or a mirror port on a switch, allowing it to examine incoming and outgoing traffic without interfering in the communication. When the system detects anomalous patterns that match pre-defined signatures or behaviors, it logs alerts for administrators to investigate. This is distinct from other systems mentioned. An Intrusion Prevention System (IPS) typically has the capability to actively block or prevent detected threats, thus working directly with the flow of data packets. Firewalls focus on controlling the traffic based on predetermined security rules, often determining what can pass through to ensure network security. A switch, on the other hand, simply facilitates data transmission within the network and does not perform analysis of packets for security purposes. This delineation between the roles of these systems highlights why the IDS is the correct answer for analyzing a copy of network traffic rather than the actual forwarded