Hi Eric,
Interesting question. I cannot anser your question directly regarding sniffing the ethernet directly with LabVIEW but this is what I can tell you about what is involved.
I wrote an ethernet sniffer about 15 years ago that ran on DEC VAXes. An associate of mine and I had access to the source code of the driver for the network interface, and found that a "permiscuous" mode was available. This mode allowed us to read all packets recieved by the interface before they where filtered or processed by any of of the code associated with OSI 7-layer model. We were restricted to reading only those packets that where valid etherenet frames (i.e. checksum failures could not be read, etc.).
So...
To duplicate this feat again on a PC platform (I'm just guessing), I w
ould start by trying to locate an interface provider that allowed the low level access you need. I would begin my search by looking into those companies that already sell sniffers. They may have *.dll's that will let you do what you are asking.
If you are developing on a UNIX type platform, this project may be a little easier, but you will still have to get at those packets before anyone else does.
I would be very interested in hearing about anyone who has done something like this in LV.
Trying to help,
Ben
