Many Wi-Fi bridging mode products exist with varying levels of functionality.
Some wireless bridges support only a single point-to-point connection to another AP. Others support point-to-multipoint connections to several other APs.
Each AP in bridging mode connects to a wired LAN. Some AP models simultaneously support wireless clients while operating in bridging mode, but others work as "bridge-only" and disallow any clients from connecting. Some APs only support bridging with other APs from the same manufacturer or product family.
AP bridging capability (when it is available) can be enabled or disabled through a configuration option. Normally, APs in bridging mode discover each other via addresses that must be set as configuration parameters.
While operating in bridging mode, wireless APs utilize a substantial amount of . Wireless clients on bridged Wi-Fi networks generally share the same bandwidth as the bridge devices. Therefore, clients tend to perform slower in bridging mode than otherwise.
In Wi-Fi, repeater mode is a variation on bridging. Rather than join multiple LANs, repeater mode is intended mainly to increase the range of a single wireless LAN by extending the same wireless signal.
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Well bridge and repeater /WDS are different..
Bridge is just the same as a wireless client.. but then connects to ethernet.. and allows multiple ethernet clients to join.. bridge is a replacement for an ethernet segment if you like.. it should be totally transparent.. ie other than being slower than ethernet it offers nothing else.
Repeater and WDS are the same thing done in different ways.. WDS is a non standard method of repeating wireless but it uses WEP security as a max and has to be configured at both ends with MAC address of the connecting device.. it is often not compatible across brands of wireless chip as it is not a standard.
The other repeater method is similar to bridge but retransmits the wireless signal and so allows wireless clients as well as ethernet clients.. it requires no configuration on the router end,, as it should appear as a client on the network. Where bridges can work very well repeaters cause terrible slow down.. the repeater box itself can either tx or rx.. so it halves the network speed.. they are flakey as the corner fish shop. So worth avoiding if at all possible..
But there are more reliable methods of repeating wireless that do work well.. a mesh is one of those methods. Also there are devices that use propriety system to achieve reliably I think apple airports can do reliable repeater but is not compatible with other brands.
If you want reliable repeater look at mesh or apple or even cisco if you have heaps of money.
DD_WRT offers better solutions than most.. because most routers won't do bridge or repeater whereas dd-wrt can offer that..If you flashed the buffalo to dd-wrt it would work as a bridge. As stated though, repeater is to be avoided.