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Ethernet Tap


I wanted to make an Ethernet tap for my UTM, so I looked around my computer supply box, and found the below items:


This seemed enough to make a TAP, following these instructions:

http://www.sun.com/bigadmin/content/submitted/passive_ethernet_tap.html


Which, about all you need to know is to hook it up like this:



Basically, when you are done, you're left with something like this (forgive that I didn't follow the color code)


Which, when all put together looks like this:


I plugged computers into port A and B, and hooked my Tap into the A-> B port,  initiated three pings from (computer A), then ran the same pings from A, but with the output showing the B->A port instead.  Below are the screenshots from computer A, and from my monitoring computer plugged first into the A->B port, then the B->A port. 



Now, whenever I need to hook up an IDS, or just want to dump packets flowing from one point to another, I can easily do this through the tap!  

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