What software or hardware tool is used to record or analyze packets transmitted over a network?

• A. Packet Sniffer
• B. Protocol Analyzer
• C. Firewall
• D. Router

Answer: (A)

Capturing and inspecting traffic on a network is done with a packet sniffer. This software or hardware tool intercepts packets as they traverse the network, records them, and provides a way to examine each packet’s headers and payload. This lets you see exactly what protocols are in use, where traffic is coming from and going to, and how data streams behave, which is essential for troubleshooting, performance analysis, and security investigations. To capture traffic on a LAN, the interface often runs in promiscuous mode or you use a mirrored port, so you can observe packets not destined for your device. While a protocol analyzer also digs into protocol details, and a firewall or router manages or logs traffic, the device specifically described as recording and analyzing packets is best captured by the term packet sniffer.