Example 1: Bridge w/ WDS enabled router
Figure 6 shows a simple "one hop" repeating setup that might be typically used to extend the range of a wireless LAN if the primary wireless router supports WDS. This setup also can be used to establish a wireless bridge between the router's wired LAN and a remote wired LAN or single Ethernet device. All you need to do for the latter mode is plug the device / LAN into the LAN port(s) of the remote bridge partner instead of making a wireless connection.
Figure 6: Bridge w/ WDS enabled router
For this example, I've paired the EnGenius ESR7750 with the NETGEAR WNDR3700. Since both are two-radio dual-band routers, we can use this hardware to illustrate a few alternate configurations and see their effect on throughput.
Perform all configuration via wired connections. Trying to do it via wireless is surely the way to madness...
Step 1: Convert the ESR7750 to an access point
We don't want the ESR7750's router firewall in the way, so we need to make it act like an access point. This is done by shutting off its DHCP server and assigning an IP address in the WNDR3700's LAN subnet, but outside its DHCP server range.
Since I have the WNDR3700's DHCP server range set from 10.168.3.100 to 10.168.3.250, I set the ESR7750's address to 10.168.3.77. Figure 7 shows the ESR7750's LAN settings page with the changes made. After the changes were saved, I connected one of the ESR7750's LAN switch ports to my LAN switch and confirmed that I was able to reach its admin screens.
Figure 7: ESR7750 LAN settings for AP conversion
Step 2: Set up one end of the bridge
Since 2.4 GHz has greater range than 5 GHz, I'll use those radios to make the WDS bridge. I'll finish up the ESR7750 settings by switching to its settings for the 2.4 GHz radio and setting it up as shown in Figure 8. Mode is set to WDS, Channel to 11 (to match the WNDR3700 2.4 GHz radio's channel) and the WNDR3700 2.4 GHz radio's MAC address (00:24:B2:51:C0:AF) is entered in the MAC address 1 box. As mentioned earlier, you can set the SSID as you wish—WDS link participants pay it no mind.
Figure 8: ESR7750 wireless settings for WDS link to WNDR3700 2.4 GHz radio
Note that the EnGenius routers don't use the MAC address : separators and don't automatically remove them if you try to paste in a MAC address with them. So you have to type in the MAC address...carefully! Note that the MAC address isn't case sensitive, but I entered the alpha characters in caps. Double check everything and save the settings.
Step 3: Set up the other end of the bridge
Now we need to set up the WNDR3700 end of the WDS link. Figure 9 shows the Wireless Repeating Function screen on the WNDR3700. All we need to do here is select the Wireless Base Station mode (Wireless Repeater is for when you want to use the WNDR3700 WDS-linked to another WDS) and enter the ESR7750 2.4 GHz radio's MAC address (00:02:6F:74:FD:48).
Figure 9: WNDR3700 wireless settings for WDS link to ESR7750 2.4 GHz radio
Note that the WNDR3700 likes the MAC address with the : separators and will automatically insert them if you just enter the MAC address without them. Note also that if you don't want wireless clients connecting to the router, you'd check the Disable Wireless Client Association box. You'd do this if you wanted to dedicate the WNDR3700 to wireless bridge duty.
Step 4: Check the Link
If you've set everything up properly, you'll know pretty quickly since you'll see wildly flashing Link and Activity lights on the two WDS link partners and the switch connecting them (if you're using one). Even though you might think gremlins have invaded your LAN, this is a good sign and is caused by the redundant network connections (two MAC addresses for the same IP address) between the APs provided by the Ethernet and WDS connections.
As soon as you disconnect the Ethernet cable from the "remote" AP—the ESR7750 in this example—the flashing should stop. Since some routers don't like being bombarded by network floods (which causes the flashing lights), I recommend you unplug both ends of the WDS link, then power up the local WDS partner first (the WNDR3700 in this example), let it come fully up, then power up the remote WDS partner (the ESR7750). This will ensure that neither box is locked up or in an odd state.
Now, leave the "remote" par where it is, open up a Command prompt (DOS command window) and ping the remote link partner's IP address (10.168.3.77 in our example). If the WDS link is working, you should be rewarded with a series of ping replies. The WDS link is up!
For some reason, the ESR7750 would not respond when I tried pinging it. But I could log into its web admin page just fine. So if you don't get a ping response from the now wirelessly-connected remote link partner, try accessing its admin pages.
Now fire up your wireless notebook, check that you can see the names of both your APs in the list of available wireless networks, then choose and connect to each AP in turn. (See why it's handy to assign different SSID's?)
If that all works, you're ready to power down the "remote" AP and move it to its desired location. Plug in the power, let it boot up, then repeat the tests. Congratulations! You've successfully made a WDS bridge!