Bridging, once the realm of hardware devices, can also be performed by a linux machine. Along with bridging comes the capability of filtering and transforming frames (or even higher layer protocols) via hooks at the Ethernet layer with the ebtables and iptables commands.

Linux can function as a bridge, the equivalent of an extremely power-thirsty switch. For now, the best place to go is the main linux bridging site.

Often ebtables and bridging are used together.