US Patent 8631100 Automatic assignment of hardware addresses within computer networks

In general, techniques are described for automatic assignment of hardware addresses within computer networks. As one example, a network device comprising a physical network interface and a control unit may implement these techniques. The network interface receives a first message from a client device requesting a layer three (L3) network address. The first message also includes a layer two (L2) hardware address currently assigned to a network interface of the client device. The control unit selects a replacement L2 hardware address for use by the network interface of the client device as a replacement for the L2 hardware address included in the first message and generates a second message having a field that specifies the replacement L2 hardware address. The network interface outputs the second message to the client device so as to automatically assign the replacement L2 hardware address for use by the network interface of the client device.