The concept of NIC Bonding (or sometimes called NIC Teaming) is that you have two NICs bonded together to appear as if they are the same physical device. I.e. They will both present the same Hardware (MAC) address. This is accomplished through the ifenslave utility, which enables the kernel to see/use only one device, while it sends out packtes via the two slave devices using a round-robbin scheduler.
Modules Involved: bonding, mii, nic_module (eepro100 in this example)
Utilities: ifenslave, mii-tool