Network Taps in Vancouver?

Anyone know where I can get my hands on a network tap in the GVRD? Doesn’t have to be anything too special, this isn’t a crazy fast line.

I think I’ve discovered that I’ve been owned and I want to check that my router isn’t up to any funny business as well.

what do you mean by “network tap” ? like a physical wire splitter, or a linux box running tcpdump, or like, a jack in the wall to plug into for “internet” access?

this is a read-only ethernet cable, used to mirror one direction of a layer-2 ethernet session to a second network port:

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EDIT: Sorry

I was looking for that except something more pluggy pluggy but that sounds like it will achieve the goal if I can find some spare cables.

you could use the female keystone jack connectors instead, and build this into a 4-port surface mount box, like these: ,

I probably would anyway, because soldering on cat5 wires can really tank the SNR of the cable, whereas you could build the other in 5 minutes with a punchdown tool and 12" of cat5 solid core.

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You’d have to be on the outside network edge of the router if you don’t trust the router, so if it’s ALSO your modem (ADSL/Fiber/Cable), then it’s a lot harder as a problem.

If you want a cheap enough way to do it otherwise, just grab a network switch that supports monitor/capture ports. Have a VLAN that just passes traffic between your modem & router, and also copies all traffic off the VLAN onto a monitor port that you can dump for analysis.

I have a little NetGear GS108Ev2 that I’ve used in the field for this explicit purpose, the only downside was having to use a Windows Vista VM to configure it in the first place. No VLAN, just dump all of ports 1-4 to port 8. Ports 5-7 pass traffic but don’t dump.

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Thank you so much both of you. Good tips. I was planning to put it right between the modem and router.

Where do you shop for such components?
Where should I go to get the tool and whatnot?

So, what you want is actually just an old hub… Or…

I have one. You can borrow it if you’d like. You’ll want USB network cards to monitor the traffic.

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I was actually exactly thinking of the throwing star tap but I don’t have one and I wanted to deal with this sooner than I think I could get it shipped. And that being the case, I think I might avail myself of your offer.

Why would I need a USB NIC specifically? Do I need 2 because duplex?

You need two as each “side” of the tap reads one. Doesn’t need to be USB, anything with two networks.
I am heading out of town tonight, and won’t be back until tuesday, unfortunately. but I can bring it to VHS then.

That’d be good I should be in on Tuesday. If I get it sorted before I’ll let you know. Thanks again.

Question for all of you:
If I have two NICs anyway and I’m not worried about reliability of the link couldn’t I invisibly MITM that traffic somehow? If so do you know how? My searchfoo is failing me.