My company is planning a new office in a typical high-rise office building. The telecom vendor proposes to run some of the network cabling in “free space”, which runs above the dropped ceiling of the office below us. They want to know if this is OK with us, or whether we insist that the cabling run in conduit. Apparently, it’s possible for someone in the office below us to eavesdrop on our network cabling somehow.
I think I saw something like this in the remake of the film Ocean’s Eleven, where they put an electronic device around the network cable (in that case it was carrying a video signal from a security camera). Is it possible in real life? Should I be worried?
Yes, it is possible. To put it in simple language, the cable acts as an antenna, transmitting whatever goes through it. However, since the data going through it is not at sufficiently high frequency, it doesn’t go very far.
Who’s working below you? If they could reasonably want to have your data and have the resources to do so, run your cables through a metal conduit.
Oh, almost forgot: If you have the cash and REALLY don’t want your downstairs neighbors pinching your data, you could go wih fiber optic cables and equipment. Not only will your data throughput be much higher, it’s nearly impossible to tap a fiber line for eavesdropping purposes.
How expensive is the equipment necessary to eavesdrop on network cabling, and how sophisticated does someone need to be to do this? If it’s something that can be done only with many thousands in equipment and a PhD in Comp Sci, it’s less of a concern.
Ignoring the far-fetched idea that someone may try to tap your network, just be sure that the cable installed is plenum-rated.
This is a fire safety item - the space above the ceiling tiles is usually the air return for the climate control system, and there are building code and insurance regulations concerning wires in this space.
If you really want to be paranoid, put fiber optic in steel conduit. More realisticaly, why are they running your cables in the downstairs ceiling and not in your ceiling?
I think that would require the network cabling to drop down to the cubicles using power poles. We don’t want that for aesthetic reasons and I think the building doesn’t permit them. So instead the telecom and power is coming from the wall or core drills.
And I assume that the cabling will be plenum-rated, but will double check with the telecom vendor.
Of course it is possible. If Bob has access to Alice’s ethernet cable, he can sniff every packet on the ether and also do other funny things by manipulating the ARP.
All Bob has to do is to splice the cable open and run an extension to his computer.
I really wouldn’t be that worried about someone downstairs tapping into it. If anything weird started happening then it wouldn’t be that hard to find the tap and see where it goes.
I would be much more worried that someone downstairs doing work in their drop ceiling saying “hm, I don’t think we’re using this wire! <snip>” and killing your network. If they run it through conduit at least the wire monkey downstairs has to break out the hacksaw to take you down.
More realisticaly, why are they running your cables in the downstairs ceiling and not in your ceiling?