ethereal and/or packetyzer are good free analyzers.
connect the preferrably to a hub instead of a switch and you will see what you are lookin for.
if you see all the different ethernet frame formats, will depend on the network you are connected to.
regards,
Robert Wullems
Network Specialist
SCP/SCE/SCM/CNX/MCP/MCSA/Network+/CNA
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If you can Sniff it, you can solve it!
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