What is the difference between a wireless repeater and a wireless bridge?

Question

Ok i have asked several questions about how to send a wireless signal over a longer distance. I have also been looking online, i have heard talk of both wireless repeaters and wireless bridges. What is the difference?

Answer 1

I've seen this recursive-definition answer repeated (pun intended) onto so many forums. Reading it, I wouldn't understand the difference -- it's the same concept explained with different terminology.  I don't consider myself an expert, but I'm going to give a go at the explanation, based on my knowledge of radio and computers (I'm a HAM operator, and a router software engineer).  At the very least, this may spark some discussion which, when read in its entirety, will act as a bridge to a better understanding of "bridge" vs "repeater."

In radio, a repeater takes an existing signal, boosts it, and rebroadcasts it.  Obviously, to avoid interference with the original signal, there has to be some technical finesse -- i.e. beam the new signal away from the original, or transmit it on a different frequency.

So, in wireless, I reckon a true repeater would be one which takes an existing signal an amplifies it, perhaps on a different frequency or channel.  A bridge, on the other hand, is a little private wireless LAN which is  connected to the original LAN. So, it has knowledge of the higher-level IP protocols, whereas the repeater would have only circuitry to receive and retransmit a radio signal.

Bridge: Understands and uses the IP protocol to propate data, potentially on different media (e.g. cable to radio, or vice versa).

Repeater: Retransmits radio signals.  In WIFI, we could probably extend that to this: Repeater = special bridge between two WIFI lans.