|Linux Advanced Routing & Traffic Control HOWTO| |Prev||Chapter
16. Building bridges, and pseudo-bridges with Proxy ARP||Next|
If you just want to implement a Pseudo-bridge, skip down a few
sections to 'Implementing it', but it is wise to read a bit
about how it works in practice. A Pseudo-bridge works a bit
differently. By default, a bridge passes packets unaltered from
one interface to the other. It only looks at the hardware
address of packets to determine what goes where. This in turn
means that you can bridge traffic that Linux does not
understand, as long as it has an hardware address it does. A
'Pseudo-bridge' works differently and looks more like a hidden
router than a bridge, but like a bridge, it has little impact on
network design. An advantage of the fact that it is not a bridge
lies in the fact that packets really pass through the kernel,
and can be filtered, changed, redirected or rerouted. A real
bridge can also be made to perform these feats, but it needs
special code, like the Ethernet Frame