Many people will still know about those old ethernet "hub"-devices - also called "dumb" device or "Ethernet signal concentrator". Did anyone ever try to "listen to ANY traffic" on such port through an interface in promiscuous mode?

Some tcpdump or tshark or wireshark probably can be used for that, right?

  • 1
    Your question isn't very clear, are you asking if anyone has ever tried to listen to traffic on a hub?
    – Torin
    Commented Mar 5, 2020 at 22:09
  • If you question is whether one can capture all traffic on a hub using a NIC in promiscuous mode via a packet capture program, then yes. I think technically wireshark doesn't do any capturing, rather it uses libpcap, but effectively wireshark is an example. If you have a different question, could you perhaps this original one a bit to clarify?
    – KevinO
    Commented Mar 5, 2020 at 22:10
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    Isn't this "network-sniffing 101" from the 1990s?
    – 0xSheepdog
    Commented Mar 5, 2020 at 22:15
  • I think the big problem here is assuming that point to point ethernet means the traffic is secure. Commented Mar 7, 2020 at 12:47

1 Answer 1


Yes that is what these devices are used for these days. I keep some around for this exact use-case.

However do not think of the functionality of an Ethernet switched-hub as a security feature. They are allowed to leak: they will do this when ever a device has not spoken, so its location is not know, or whenever the number of slots in the table is full, and the switch forgets about a device. The switching is only for performance, NOT security.

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