0.8-0.9Kb here - I know it's ARP, as I could count ARP traffic on my network card utility.
The only easy way I can see to avoid screwed up bandwidth monitor software, is to work through a router.
The other thing, I have the option to add SNMP to the network card, and I know of one free SNMP based monitor tool.
http://www.snapfiles.com/get/itindicator.html