31 Juli, 2011

Linksys E4200 - HOWTO: Wireless Highspeed Bridge

Use 2 Linksys e4200 routers to "bridge" some distance in your house where cables cant go or would be too much work...

My situation: I wanted to connect my livingroom (Satellite HDD Receiver, Wii, PC) to my homelan. I had this before - but only using powerlan (network over the powerline). This is slow - no matter what they write on their ads... (around 0,5MB/s)

So I decided to buy 2 of the currently best routers and get them connected at the currently highest available wireless speed - 450mbit on 5Ghz (802.11N).
The good on this routers: they can do both - 2.4Ghz and 5Ghz at the same time. So you can bridge two of them together and have both acting as access-points - without loosing much performance. Another great aspect of the e4200: the wireless signal is really strong - giving you wifi nearly everywhere in a big house!

Step1 - download DD-WRT firmware
On the standard firmware as they come, they don't have the option to be wireless bridges, or WDS repeaters or however you may call it...
So download the very good open source alternative: DD-WRT
I use: DD-WRT v24-sp2 (04/13/11) std-usb-nas
Download here or search "e4200" at dd-wrt.

Step2 - do a 30-30-30 reset:
- while running, press and hold the reset swith on the router for 30sec
- unplug the power cable while still pressing the reset swith - wait another 30secs
- then replug the power and hold the reset for another 30 secs
I'm not really sure if this was neccessary - but I did like I was told...

Step3 - install firmware
To install it, you just follow the normal firmware upgrade procedures (not sure now where this is at the standard routerpages - as I have only the modified software on both routers here). On DD-WRT they write a good FAQ how to install the firmware.

Step 4 - setup both routers:
I'll just copy my config here and hope you know how to adapt these settings to match your homelans IP address range...

Router1 - Main accesspoint - connected to homelan and internet:

Interface WL0 (normal Wifi 2.4Ghz)
Wireless Mode: AP
Wireless Network Mode: mixed
SSID: normalwifi
Channel: auto

Interface WL1 (Bridge WIFI - 5Ghz)
Wireless Mode: AP (important: both routers have to be AP - not client bridge as I thought!)
Wireless Network Mode: N-only 5Ghz
SSID: bridge
Channel: 120 (choose what you like - but the same on both routers!)
Channel Width: 40Mhz
Control Channel: upper
SSID Broadcast: disable (could be enabled at first tests)
Network config: bridged

Wireless Security:
wl0: WPA2 Personal mixed / TKIP+AES
wl1: WPA Personal / AES

WDS Settings:
LAN and the MAC address of your other routers WL1 mac address (can be found on his configpage at the same spot as you are here (Wireless / WL1-WDS)
This tells the router here which other router can connect as a bridge to him. The same has to be done on the other router with this routers MAC (found right here). Confuesd? :-)

Router2 - router in livingroom:
Basicly just setup both routers the same way. Only difference is in the WL1-WDS section where you have to specify the MAC address of the other router.

If you did everything right, you can now unplug the LAN cable from the "livingroom" router (.251) and try to ping it - if it works - congrats - your wireless bridge works! (coming here took me nearly a day - if you were faster - your either more intelligent, luckier or my guide helped :-)

You can see on the Status / Wireless section under the point "WDS Nodes" if there is the other router. Can take some time - but if you have a working bridge - it should come up here and also show's you your signal-quality - mine is 24% through 3 walls - not perfect - but still gives me around 5-6 mb/s (megabytes per sec - or 40-48MBits) that's far more I ever got with other wireless systems and comes close to 100 MBit Lan cable speed. This way 1GB file transfer only takes ~3mins!

Tip on restarting the routers (and their bridge):
I found, that if I only restart one router - the bridge wouldn't work after the restart until I use the right order:
first restart the client - livingroom router (although both should be equal)
the wait some time and then the "main router" - connected to the internet)
So I set timers on the powerplugs and let the livingroom router start earlier in the morning...
Since I did this - the bridge works without a problem. You surely could let them run forever - but I like to save power by shutting down devices in the night...

If you read this and it helped please let me know by commenting here.
or read and comment on Experts Exchange here: Linksys E4200 - HOWTO: Wireless Highspeed Bridge



TechBri hat gesagt…

Hi. I am planning to pick up another E4200 and set this up tomorrow. One difference though. I have another existing router so I intend to run both units in a bridge environment and disable NATand use them only as APs but bridge the 5GHz together as you described. Do you know how to do this?

TechBri hat gesagt…

I bought a second e4200 and loaded the dd-wrt firmware you linked to in your post. I followed your instructions exactly for both routers except I set the them to disable the wan interface and add it to the switch. I then set them to router mode instead of gateway mode to disable NAT as I have another firewall that provides nat and dhcp. Once I set everything up a d disconnected the ethernet cable between the routers, I could not get to the Internet through the bridge unit. I started over several times and double checked the instructions but it didn't work. I am a systems administer and network engineer for a living so I hope i had everything right. Any suggestions? Thanks.

Schim hat gesagt…

Sorry to read you didn't succeed yet. You set router mode instead of gateway to disable NAT? I would do the opposite - but maybe this was just a typo. NAT shouldn't be a problem here - if you set the wan interface to be lan port there wouldn't be something to nat here at all. DHCP can be just left turned of (I had it running but had strange probs so I turned it off again and we use our old netgear routers dhcp alone again - works better).

So again: I would try setting both (or all three in your case?) to AP Mode. Maybe the dd wrt forum guys can help you further? there sure some smart guys there...

good luck,

TechBri hat gesagt…

Well, I setup two E4200's in a lab today and restored them to factory defaults. Next I did the 30/30/30 reset and then installed the DD-WRT firmware. I setup the primary on a DSL line and used the WAN interface as DHCP and left NAT alone. I then setup the second E4200 and connected it's WAN port (disabled and added to switch) to a LAN port on the primary unit. Once I completed all of the steps, I disconnected the cable between the units. I then connected a laptop to the second unit lan port. (Note that DHCP was running on the primary unit as I needed something to do DHCP in the lab setup. ) After connecting the laptop, I noticed that I did not get an IP from DHCP and could not ping the primary router IP. Of course with the cable connecting the units, I did not have the problem. I was hoping if I replicated your setup, I could get it to work and then could try switching to access point mode but it didn't work out.

I posted an inquiry on the forum today and pointed to your instructions and basically just got a response telling me to read their forums and that I was getting any help. Disappointing but not too surprising.

I am not sure where to go from here. I may just have to return the units.

TechBri hat gesagt…

I got the routers working! I think there is a small typo in your instructions. Under wireless security, interface wl1 needed to be set to WPA2 with AES not WPA. I reached out for some help on the dd-wrt forums and some guy named murrkf felt the need to hassle me about reading the documentation and to tell me you were uninformed. Based on his response, I was ready to quit but I kept trying and got it working. Thanks for the help. I will hook them up here at home tomorrow and will run some tests against them to see how fast the solution is.

Anonym hat gesagt…

Looks good to me.
Seems the supportability of the router is only recent...
Really glad to see a recent N linksys supported...

Anonym hat gesagt…

Hi, I setup two E4200 Routers WDS bridge. Bith Modes are AP. and same SSID and with mac address security. SSID broadcast is also disable for high security.
You can contect me at shujat29@hotmail.com

Mary Walker hat gesagt…

You and your family are going to probably suffer some sort of brain tumor or something when you're 70+ years old due to all the wireless signals traversing your home. I'm sure no one knows the long-term affect of this due to the rapid increase in bluetooth, wireless, and other frequencies.... visit- Linksys Router Technical Support also call Toll Free No 1-800-231-4635 For US/CA.

Linksys Router login hat gesagt…

Very helpful Post.
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