You can find packet capture files on many devices, including routers, switches, firewalls, wireless access points, and computers. Some packet capture products let you view live network traffic, while others allow you to save captured packets for later viewing.
Captured packets can reveal a lot about your network traffic. In some cases, you can tell whether someone accessed a particular webpage by looking at the packets that traveled between your web browser and the server hosting that webpage. If you suspect that malware is attacking your system, you can look at captured packets to determine where that malware came from and what it did once inside your network.
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