Neither is, by the way, moving network cables around to get to a point in the network appropriate for capturing the right kind of traffic.
However, what if you cannot use these tools on your end devices? Many times, this type of diagnosis is needed in a highly-available datacenter-type environment, and installing one of these tools is not acceptable. Many times, it is helpful to install/use one of these tools to figure out exactly what’s traversing the network, by seeing the frames and packets themselves, in a visual way. Even developers use these tools to diagnose issues with applications utilizing network resources. Those in the networking industry know that tools like tcpdump and wireshark are crucial for deeply investigating network issues. Often, especially in medium to large networks, it’s crucial to monitor the traffic traversing your networks.
