Universal Wireless Repeater

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This How-To provides step-by-step instructions for creating a Universal Wireless Repeater appliance: a device that you can place anywhere and it will wirelessly repeat the strongest signal, onto another wireless network (with or without security). This functionality is also known as Wireless Client Bridge, or Range Expander. Unlike WDS, once you have this appliance setup, it will work with any open network.

Architecturally the repeater connects to another wireless router as a client, getting a single IP address via DHCP. Effectively the SSID network it connects to becomes your ISP. Therefore you (the client) will operate in your own IP address space, which is different from address space the repeater connects to.

For example:

In a given neighborhood, there are 3 open access wireless networks, jojo, linksys and internetmad. The repeater automatically receives an IP address from jojo. Let's say jojo is using, and your DDWRT router receives the address The repeater is configured to use From your laptop, you associate with the SSID "repeater" and you receive the address via DHCP. As far as your laptop is concerned you are talking to repeater. As far as repeater is concerned, its gateway is "jojo" and jojo probably has another gateway via cable modem or DSL.


It takes me just a couple minutes to follow these instructions (but I've done this before).


1. Install DD-WRT v24 beta (v23 will not work).

  • Build 2006-0911 is known to be stable for repeater mode. Users also report success with newest builds (2007).
  • Keep ethernet cable connected for these instructions (to have connectivity across wireless network changes).

2. Go to tab "Setup", sub-tab "Basic Setup":

  • Change "local IP address" to a unique subnet (different than device you wish to repeat), such as
  • Save settings.


3. Point your browser to the new IP address you chose in the previous step. Go to tab "Security", sub-tab "Firewall":

  • Uncheck all check boxes and set firewall to "disable".
  • Save settings.


4. Go to tab "Wireless", sub-tab "Basic Settings":

  • Set Wireless Mode to "Repeater"
  • Click on "Add" under Virtual Interfaces, and enter an SSID (such as "repeater") and set "Wireless Network Name (SSID)" to the network you wish to repeat (and AP Isolation is "disabled" and Network Configuration is "Bridged"). If you want the source network (the one your repeating) to be dynamically acquired, see steps below.
  • Note: the screenshot is from build 2006-0911. In newer builds there is a Network Configuration option (Bridged/Unbridged) for both Physical and Virtual Interfaces. For both options, set Network Configuration to "Bridged".
  • Optional: Set Wireless Channel to "Auto" (or your preferred channel), and set Sensitivy Range to "0" for performance enhancements.
  • Click "Save Settings".


5. To repeat any network dynamically (make this a universal wireless repeater), the following will make the repeater connect to the first available SSID:

  • Go to tab "Administration", subtab "Command".
  • Copy and paste the following into the edit box:
nvram set wl_ssid=""
  • Click the Save Startup button.
  • Note: this will not automatically repeat secure/encrypted networks. If your source network uses WEP or WPK, enter the ssid under the Physical Interface in step 4 instead, and proceed to the next step.

6. You may use security (WEP, WPA, etc) in repeater mode. An example application of this would be to make the repeated network private (for your use only).

  • Go to tab "Wireless", sub-tab "Wireless Security".
  • Setup WEP (or other security) under virtual interface.
  • Configure your client/computer to use the same security.


  • Notice in the screenshot above you may also configure security for the physical interface (source) network if you wish to repeat a secure network. In the example this is disabled. If you enable this, the dynamic repeating functionality may not work (since you're hard configuring the source network).
  • Note: for build 2006-0911, only one interface can have security - not both simultaneously. This is fixed in latest builds (2007-0109 and newer). See "Known Issues" below.

7. The first time you connect to the repeater (wirelessly), or after disconnect, you may need to perform a "repair wireless network connection". For example, in XP, right click on the wireless icon and select "Repair".


8. If you wish to dynamically repeat the STRONGEST signal (a more sophisticated version of #5 above) please read the AutoAP Wiki Article.

AutoAP is a script that continuously scans for open wifi connections, tests them for validity, and connects to the strongest signal. If the connection is lost, the script scans again and finds the strongest valid signal again, and maintains a continuous connection to the internet in a mobile or portable environment. The script paremeters are highly configurable, including ability to configure secure connections.

9. For optional repeater performance enhancements:

  • Go to tab "Wireless", subtab "Advanced Settings". Set "Preamble" to "Short". Set "Xmit Power" to higher than default (I use 200). Click "Save Settings".


  • If you are having problems getting repeater mode working, first setup Client Mode or Client-Bridged Mode as a test. Once you have client mode working, then switch to repeater mode (keeping all your other settings) - verify its still working, and then add the virtual interface(s).
  • The first time you connect to the repeater (wirelessly), or after disconnect, you may need to perform a "repair wireless network connection". For example, in XP, right click on the wireless icon and select "Repair".
  • See Known Issues below.


Your testing results and enhancements are appreciated: