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Entry type: FAQ Entry ID: 23584230, Entry date: 01/09/2019

How do you set up a WDS connection between SCALANCE W modules?

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WDS stands for "Wireless Distribution System" and is the wireless connection of multiple access points (APs) with each other in order to extend the range of a radio network without having to connect the extension access points via Ethernet.

In normal operation the access point is used as the interface to a wired network and communicates with WLAN clients. However, there is also the case when multiple access points have to communicate with each other with the aim of extending the range, for example, or establishing a wireless backbone. This sort of operation is possible with WDS (Wireless Distributed System).

If you use WDS in a SCALANCE W, you have the following advantages:

  • You can configure WDS on all VAP (Virtual Access Point) interfaces in the SCALANCE access point.
  • With the "Only WDS" option you can define per VAP interface whether the access point should only support communication via WDS.
  • You are given two options when configuring WDS. The WDS partner can be configured both via the WDS ID and via its MAC address.
  • You can use WDS unencrypted or encrypted with WPA2-PSK encryption.

When using WDS the following conditions must be fulfilled for all participating access points:

  • All access points that are to communicate with each other must use the same channel, the same transmission procedure and the same data rate. You cannot use automatic channel search with WDS.
  • For encryption you can choose between WEP and WPA2-PSK. It is recommended to use WPA2-PSK. You configure the security settings in each of the assigned VAP interfaces: "Security > WLAN > Basic". You cannot use authentication via RADIUS server for a WDS connection.
  • It is not useful to select the WDS operating mode in the transmission procedure IEEE 802.11h. In the WDS operating mode all the access points must use the same channel.
  • WDS can only be configured if the SCALANCE W is being operated in the Access Point mode. If the SCALANCE W is configured as client, you cannot establish a WDS connection.
  • The WDS partners must be in the same subnet.

Configuration Instructions
Proceed as follows to configure a WDS.

1. Use the wizard to install your WLAN interface. This involves the following points:

  • Regional and Language Options setting
  • IP address
  • Definition of the antennas
  • Wireless settings
  • Security settings
  • Access Point settings

2. When you have finished with the wizard you open the "Interfaces > WLAN" menu and go to the "Allowed Channels" tab. Make the following settings:

  • Enable the option "Use Allowed Channels only".
  • Disable the option "Select/Deselect all".
  • Check the appropriate checkbox for the desired channel number.

  • Click the "Set Values" button.

To establish a WDS connection you must use the same channel number for the WDS partner.

Fig. 1

3. Switch to the "AP" tab. Make the following settings:
  • In the row of your VAP port you define a WDS ID in the "WDS ID" column. The WDS ID must not be longer that 32 characters. The ASCII code 0x20 to 0x7e is used for the WDS ID.
  • You can also choose to enable the option "Only WDS".
  • Click the "Set Values" button.

To establish a WDS connection you must enter this WDS ID for the WDS partner.

Fig. 2

4. Switch to the "AP WDS" tab. Make the following settings:
  • In the "Connection over" drop-down list box you select the required VAP interface.
  • In the "Partner ID Type" drop-down list box you select the item "WDS ID". The "Partner MAC" input field is grayed out.
  • In the "Partner WDS ID" input field you enter the WDS ID of the WDS partner.
  • Enable the port.
  • Click the "Set Values" button.

You defined this WDS ID in the WDS partner in the menu "Interfaces > WLAN > AP".

5. Switch to the "Data Rate" tab.

Fig. 3

If you use the default settings, you do not have to make any changes here.

6. For "WLAN 1" you enable the option "Use selected data rates only". Make the following settings:

  • In the "Radio" drop-down list box you select the item "WLAN 1".
  • In the "Enabled" column you check the appropriate checkbox for the required MCS Index.
  • Click the "Set Values" button.

To establish a WDS connection you must set the same data rate for the WDS partner. 

Fig. 4
7. Repeat steps 1 to 6 for the WDS partner.
8. To view the state of the WDS connection you open the menu "Information > WLAN" and go to the "WDS List" tab. In the "State" column you can see the state of the connection.

Fig. 5

Alternatively you can also view the "WLAN Authentication Log". The log is available in the menu "Information > Log Tables".
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