Fri Oct 07, 2016 7:38 am
Bridge is software switching, master port is hardware switching. Use master ports to switch multiple physical interfaces where you want full wire speed. Use bridges to connect those master ports together, possibly with wlan ports as well.
With hardware switching alone there is no way to place a wired Ethernet segment on the same broadcast domain as a wireless segment, or interconnect different switch chips. For that, you need to use software switching (bridge functionality).
In a WISP situation, I usually do not bother with master/slave ports because it is rare, given the limitations of wireless PtMP radio equipment, that you will ever be in a situation where you are switching gigabit traffic; in such situations, where you are usually switching <100Mbps, hardware switching introduces additional complexity of configuration while decreasing CPU load only minimally.
The difference is much greater when dealing with traffic nearing gigabit speeds; any switching at this rate that you can remove from the router CPU and offload to the switch CPU makes it worth setting up master/slave, even though it makes the configuration a little more complicated.