How to sniff a switched LAN by plugging the laptop into a switch port There is a switch-based LAN without encrypted traffic. I want to sniff **ALL** its traffic (ARP, TCP, ICMP, etc.) by plugging the laptop into one of the switch port. Then run the software on the PC to sniff the network traffic. Of course I will provide an authorized IP address to my laptop. It is an authorized test in lab environment. How can I do the sniffing? What sniffing software should I use?

The easy part: Use Wireshark for the sniffing.

The hard part: In a switched network you need support from the switch to get all the traffic. It is called "port mirroring", "span port", "monitor port" depending on the vendor. Without control over the switch you will not be able to capture all traffic.