Repeater Bridge

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You should now be able to connect wired clients and wireless clients to the newly configured Secondary router. They will receive IP Addresses from the Primary Router and will be able to use the Internet connection supplied by the Primary Router. You should now be able to connect wired clients and wireless clients to the newly configured Secondary router. They will receive IP Addresses from the Primary Router and will be able to use the Internet connection supplied by the Primary Router.
 +
 +Also take note of the fact that all repeaters, including this Repeater Bridge mode, will sacrifice half of the bandwidth available from the primary router. This is a result of the repeater taking turns talking to not just one partner, but to two, and having to relay the traffic between them. As long as your bandwidth requirements are within this halved bandwidth amount there will be little or no reduction in "speed".
== Troubleshooting == == Troubleshooting ==

Revision as of 23:48, 7 July 2008

Wireless Bridging is used to connect two LAN segments via a wireless link. The two segments will be in the same subnet and look like two Ethernet switches connected by a cable to all computers on the subnet. Since the computers are on the same subnet, broadcasts will reach all machines, allowing DHCP clients in one segment to get their addresses from a DHCP server in a different segment. You could use a Wireless Bridge to transparently connect computer(s) in one room to computer(s) in a different room when you could not, or did not want to run an Ethernet cable between the rooms.

The limitation with standard Bridging is that it only allows wired clients to connect to the secondary router. New in v24 is Repeater Bridge mode which allows extension of the LAN via the secondary router and but also allows wireless clients to connect to the secondary router. This is a perfect way to extend the wireless range of your existing network while still allowing wired clients to connect to the secondary router.

Reference Image
Reference Image


In the case in which we are interested, a secondary router running DD-WRT v24 is configured as a Repeater Bridge between a Primary wireless router (of any make/brand/FW) allowing the above configuration.

Assumptions:

Primary router is configured in a 192.168.1.X subnet and leases DHCP address in the same pool. Secondary router is running DD-WRT v24

No security setup will be covered in this Wiki. It will be up to the user to setup security between the Primary and Secondary routers

Note , it is advisable to set the router first in client bridge mode and get it working correctly , once client bridge works , then proceed to setting up repeater bridge

Contents

Instructions

A very simple step-by-step description to connect a Router running selected DD-WRTV24 firmware in Repeater Bridge Mode.

Confirmed working/non-working V24 firmware:

  • RC5 - works
  • RC6.2 - does not work
  • RC7+ - works best (separate builds with new or vintage drivers)
  • V24-final, V24-VINT-final - Works

To enable Bridge-Mode between two Routers, the Primary router has to be in AP mode. The Secondary router running DD-WRT v24 as Repeater Bridged

  1. Restore Factory Defaults on Secondary(DD-WRT) Router
  2. Connect to the secondary router via wired or wireless client keeping in mind the dd-wrt default settings for dhcp pool and ssid
  3. Open the Wireless -> Basic Settings tab
    • Wireless Mode : Repeater Bridge
    • Wireless Network Mode : Match Primary Router
    • Wireless Network Name(SSID) : Match Primary Router
    • Wireless Channel : Match Primary Router
    • Wireless SSID Broadcast : Enable
    • Network Configuration : Bridged
    • Save Settings
  4. Virtual Interfaces Section
    • Add
    • Wireless Network Name(SSID) : Different from Primary Router
      • [NOTE] - being a bridged setup and all DHCP is being done by the host AP - it is possible to use the same SSID as the Host AP for this Virtual SSID name. This will allow roaming hand-offs between the 2 units. redhawk Confirmed --ChuckMcB 00:34, 31 March 2008 (CEST)
    • Wireless SSID Broadcast : Enable
    • AP Isolation : Disable
    • Network Configuration : Bridged
    • Save Settings
  5. Open the Setup -> Basic Setup tab
    • Connection Type will be: Disabled
    • Set STP for Disabled (Enabled sometimes can cause connection problems) redhawk
    • IP Address : 192.168.1.2 (Assuming Primary Router IP is 192.168.1.1)
    • Mask : 255.255.255.0
    • Gateway: 192.168.1.1 (again assuming Primary Router IP is 192.168.1.1)
    • Assign WAN Port to Switch : Checked or Unchecked - your choice
    • Save Settings
  6. Open the Security -> Firewall tab
    • Uncheck all boxes
    • Disable SP1 firewall
    • Save Settings
  7. Open the Status -> Wireless tab (If this step is performed the repeater bridge may or may not work - skip to Step 8) redhawk Worked on two different routers without this set, recommend remove --ChuckMcB 00:34, 31 March 2008 (CEST)
    • Wiviz Survey (or Site Survey)
    • Join Primary Router
    • Continue
  8. Open the Administration tab
    • APPLY Settings (In V24 after 07/04/07...use Save for previous versions)


You should now be able to connect wired clients and wireless clients to the newly configured Secondary router. They will receive IP Addresses from the Primary Router and will be able to use the Internet connection supplied by the Primary Router.

Also take note of the fact that all repeaters, including this Repeater Bridge mode, will sacrifice half of the bandwidth available from the primary router. This is a result of the repeater taking turns talking to not just one partner, but to two, and having to relay the traffic between them. As long as your bandwidth requirements are within this halved bandwidth amount there will be little or no reduction in "speed".

Troubleshooting

Note: i have noticed that in almost every case that going from factory default ap mode to repeater bridge mode will fail without first setting up the router for client bridge mode first , so i suggest you setup client bridge or wireless bridge first , then continue on to change the router to repeater bridge

http://www.dd-wrt.com/wiki/index.php/Wireless_Bridge

SSIDs

Under "Wireless -> Basic Settings", you must use the primary router's SSID for the physical interface and a new SSID for the virtual interface. Some people argue the physical interface can also be the same in order to support roaming (see Repeating Mode Comparisons)

NAT

  • Problem: On v24RC4, packets go through NAT in the direction to the gateway.
  • Solution: To disable this, go under the Advanced Routing tab in set-up and change the mode to "router" instead of "gateway". Also have routing disabled under the Admin tab. (TODO: Confirm).

Wireless Clients cannot connect to Repeater

  • Problem: LAN clients can connect to the repeater, but wireless clients can't connect at all.
  • Solution: Repeater-bridge is broken in early versions of RC6, try downloads/others/eko/RC6-8733 or higher

Wireless Clients have no Internet

  • Problem: Wireless clients can connect to the AP, however they can't connect to the internet.
  • Solution 1 : Followed the instructions listed above and had to do the following: My host wireless router had the SPI firewall enabled (running dd-wrt 23SP2) and my wireless AP (running dd-wrt 24RC3) had the SPI firewall enabled. Per the instructions above I disabled the AP router SPI firewall but also had to disable the host routers SPI firewall. Once I did this the clients attaching to the AP could get to the internet (external access). Additional note: In my case my the host wireless router is directly cabled to the ISP hardware router which does have the firewall enabled.
  • Solution 2 : The instructions on this page worked great for me, i just set up 3 Asus 520GU as wireless repeaters connecting to a standard netgear wireless AP. Once i setup dd-wrt as wireless repeaters on the asus routers i was able to access the internet via the LAN, not wirelessly. my computer would connect but with limited or no connectivity giving me some really strange IP address. to solve this issue of no internet via the wireless connection i did the following (windows xp pro)

1) network connections 2) right click wireless adapter, click properties 3) scroll down to tcp/ip, highlight, then click properties 4) manually add all ip/subnet/gateway/dns information example

ip: 192.168.1.6 subnet: 255.255.255.0 gateway: 192.168.1.1 (this is the netgears ip address. its the DHCP server) DNS: 192.168.0.1 (this is the main router's address directly connected to the ISP.

good luck, i hope this helps!

Security

Keep in mind any security settings will need to be configured including MAC filtering in order for the Secondary Router to connect to the Primary Router and also for clients connecting to the Secondary Router to gain full access to the connectivity of the Primary Router. There are some factors to consider when setting up Security for Client Bridge mode that may or may not be factors when setting up Repeater Bridge mode. I simply have not experimented with this.

[NOTE {Montrealmike}]Also when your adding WEP,WPA,WPA2 etc... between the AP and the repeater bridge you have to start with the AP first; then the repeater bridge.When you enable security on the repeater click save not apply, then click on the administration tab scroll down to the bottom and click apply settings. You will then have to power cycle the repeater twice ( unplug and plug back in twice ) in order for the repeater bridge and AP to synchronize. This has worked for four repeater bridges for me.

Edit - GeeTek - We know you are trying to help, but there is no logical reason to do a cold boot on anything 2 times in a row to make it work. Please double check your information before posting such advice. Some of the poor freaks out here may actually believe it to be true.

Edit - Altair - In my experience the above advice of power cycling the router has been confirmed. I spent 20 minutes trying different things to no avail before I finally gave in and tried power cycling it twice (I honestly didn't believe it would do anything). After the power cycle it has been working flawlessly.

Edit - pmiller - I can also confirm the power cycling to sync the repeater to the AP. You can confirm that the repeater has syncronized with the AP by going to the Status>Wireless tab on the AP and viewing the MAC address of the repeater with some % signal quality value. Before doing 2 power cycles on the repeater, the MAC address would display on the AP's Status>Wireless tab, but with 0% signal quality. After the power cycles the % quality displayed around 30%. I played around with other security settings later on the AP and found the 2 power cycles to be unnecessary after the 2 had originally sync'ed- no idea why this would work, but it did. I had some difficulty at first because I had security enabled on the AP as WPA2-Personal Mixed, which is basically WPA2-AES or WPA-TKIP simultaneously. The repeater is unable to connect with the AP in this mixed mode; rather you must choose between WPA2-AES or WPA-TKIP . I have now switched both my wireless security settings to WPA-TKIP (physical and virtual) just for simplicity, though in theory the virtual need not match the physical. Your security is as good as the weakest link. For those having trouble, I would turn off all security and turn on SSID broadcast first, then once you get a good sync turn on security on the AP first, then the repeater.

Edit - aselvan - I have this setup on identical hardware (i.e. Linksys wrt310n) for AP and repeater running identical DDWRT (v24 standard generic). However, I can't get the WPA2 working between the repeater unit and AP no matter what combination I tried-- the repeater and AP can't connect, however, WEP and WAP works. Anyone have any idea?

Accessing Both Routers?

With this setup, I have full access to both routers — which runs contrary to a lot of the notes concerning Client Bridge mode. One router is http://192.168.1.1, and the other is http://192.168.1.2. I can access both from either side of the bridge. There is no need to change any settings or IP addresses or the like with this setup in order to do so!

MAC Filtering

For those of you who have enabled MAC filtering on your Primary router, you need to add the WLAN MAC address of your Secondary router to the permitted MAC filter list of the Primary router. This is different than the MAC address printed on the bottom of the case, you can find it by going to Status->Wireless and the top line will list the internal MAC address. Of course, you will want to add the MAC filter list to the Secondary router. This should be setup prior configuring your WPA, WPA2, etc. settings otherwise you will spend some time pondering why the bridge isn't working.

[EDIT - Redhawk] - The wording here was a little confusing. Once I used the Wireless MAC address then all worked correctly....the MAC filter address on the Primary router needs to be the "Wireless MAC" address listed on the Router Status page and not the LAN MAC address . (Use Router MAC +2) - Yes...I know it says WLAN but for an noob doing this procedure it could be confused.


Special thanks to Griminal for providing a basic graphic which I modified for this Wiki Entry.

See Also