Wireless Distribution System

The Wireless Distribution System (WDS) is a method of addressing data frames in Wireless Local Area Networks based on IEEE 802.11, which allows sophisticated topologies in 1999 was defined in a nutshell, and is often misunderstood. How WDS is to be used, leaves open the definition.

This addressing is creating the basis for ad -hoc networks, gateways to local area networks of other standards such as Ethernet, and example for Bridges using wireless technology. For ad -hoc networks and gateways, the data frames are provided with three addresses for all other purposes with four addresses:

This 4- address format multiple applications are possible and completely exempted from WDS.

Wireless Backbone

One possible application of WDS is a wireless network consisting of multiple wireless base stations Wireless Access Point ( AP). So you can achieve a greater coverage than a single access point without a cabling of all base stations. Only the power of each base station is required. WDS can be integrated on a single WLAN interface on the AP as well as several.

Technology

Single-radio WDS uses the wireless interface both for connection to a neighboring access point as well as for the supply of the WLAN users (clients). The data transmission rate of the interface is halved, as the packets have to be sent twice. Therefore, WDS can be better realized with dual-radio access points. Here, a service of the AP to connect the next access point is used, a second for the clients.

Alternatively or in addition, it is also more complex techniques such as radio, beamforming or multipath propagation (MIMO) use to counteract a reduction of the bandwidth even when using a single radio channel or even prevent. That is, in practice, instead of relatively rare.

In the best case, use transmitters with different standards (eg 802.11a, and 802.11n 802.11b/802.11g ). The individual access points must be known to the WLAN MAC addresses of other access points. In addition, everyone should use the same SSID ( mandatory for WPA encryption ), the same channel and the same network key (WPA or less secure WEP) use, otherwise roaming or handover, ie the "flying" change from one is not possible for another access point.

WDS modes

A distinction is made between the bridging mode (direct connection, point- to-point), in which two configured as a WLAN Bridges APs communicate only with each other ( without that other clients can connect ) and the Repeating mode, in which multiple access points with each other via WDS are connected and may additionally wireless clients connect (Point-to - multipoint). In the latter mode, the WLAN can thus be "extended", but most devices work only with WEP encryption.

Comparison with alternative wireless range extensions

WDS is often confused with the Universal Repeater mode, which is supported by many access points.