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Back when I was just getting into networking, ethernet hubs were common, and switches were a fancy, expensive alternative. Then the price of switches came down so much that hubs became pretty much obsolete, except when you actually didn't want switching - as wikipedia points out, "hubs can still be useful in certain circumstances," such as "for inserting a protocol analyzer into a network connection." That's a particular use case I've come across several times, especially at work -- I haven't yet learned all the ins and outs of configuring RSPAN (Cisco's implementation of port mirroring) on Cisco switches, and sometimes it'd really just be easier to plug a laptop into a hub with the system I want to monitor.

The only problem is, I can't actually find any place to buy a hub. Small switches start at $25, so I'd expect to be able to find a hub even cheaper... except I can't actually find one at all. A google product search for "ethernet hub" instead finds ethernet switches and usb hubs instead, plus a few expensive ethernet devices that I'm not quite sure what they are :)

Does anybody actually make hubs anymore? Or am I going to have to hang out on ebay and hope to find someone who's getting rid of one, and who knows enough about what they're selling to describe it accurately? A gigabit-compatible hub would be ideal -- do those even exist? Wikipedia only talks about 10/100 Mbps hubs.

Josh
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4 Answers4

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If your application for a hub is "inserting a protocol analyzer into a network connection", the modern answer is a switch that features "port monitoring" or "port mirroring", in which one switch port is configured to emit all packets to and from another specified port.

For example, the Netgear Unmanaged Plus switches provide this very function, at 1Gb and 10Gb. The Netgear GS105Ev2 is a 5-port 1Gb switch in this line, available for $40 on Amazon.

Jacob
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Jamie Cox
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Amazon to the rescue.

Unfortunately it's a special product now (people who want them really want them and can't use something else) so the prices may be higher than you expect.

EDIT:

Also you will NOT get a gigabit hub. You won't find PCI-E video cards to use on a 386 motherboard, either...:)

JNK
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4

If hubs are hard to come by, another option might be to buy a Wi-Fi router that runs dd-wrt, which it should be possible to configure port mirroring on.

Josh
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3

Another answer from Amazon : Dynex DX-EHB4 - Hub - 4 ports - Ethernet - 10Base-T - DC power - external, 1 new from $22.99 and 16 used from $1.84.

Just asking for Ethernet Hub in Electronics will get you 355 products (most of them actually switches).
You may reduce the results further by price etc. to narrow the research.

harrymc
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