So what the heck, if it can be done, I might as well do it. OTOH I don’t know every damn thing and have been wrong before. As I said earlier, I doubt that we will see the results he is expecting. He fully believes that we need to put the network card into promiscuous mode. However, he has been like a bull dog on this topic. I have bullied him into arranging a meeting with me and them as it is my belief that he either misunderstood them or they are BSing him because they want to sell him something beyond the original device. I think I can get away with saying that he is hoping to interface to a specific device whose manufacturers have told him needs a network card to be in promiscuous mode. We develop for the government and so I’m not sure what I’m allowed to say about what we are doing… If the computer is attached to a fairly modern ethernet switch, rather than the older-fashioned and now largely obsolete hub, then incoming packets will only be for the specific machine anyway (except maybe a few things that are broadcast, but probably not very interesting) What is it that he is actually hoping to achieve? Is he hoping to be able to eavesdrop on general traffic on the whole network? - because that’s only really possible on a network that uses a hub, or a switch with a promiscuous port.

Wireshark promiscuous mode windows