An Access Point can be either a main, relay or remote base station. A main base station is typically connected to the wired Ethernet . A relay base station relays data between remote base stations, wireless clients or other relay stations to either a main or another relay base station. A remote base station accepts connections from wireless clients and passes them to relay or main stations. Connections between "clients" are made using MAC Address es rather than by specifying IP assignments.
All base stations in a Wireless Distribution System must be configured to use the same radio channel, and share WEP keys if they are used. They can be configured to different Service Set Identifier s.
WDS may also be referred to as repeater mode because it appears to bridge and accept wireless clients at the same time (unlike traditional bridging). It should be noted, however, that throughput in this method is inversely proportional to two raised to the power of the number of "hops",1/T = 2^h or T = 2^(-h), approximately, where T is throughput and h is number of hops (WAPs) as all traffic uses the same channel. For example, client traffic going through one relay station before it reaches the main access point will see at most half the maximum throughput that a directly connected AP would experience and a client two hops from the directly connected AP will see at most one quarter of the maximum throughput seen at the directly connected AP.
WDS may be incompatible between different products (even occasionally from the same vendor) as it is not certified by the Wi-Fi Alliance .
- Apple Inc 's Airport Extreme 802.11-(pre)N, Airport Extreme 802.11b/g and Airport Express are all able to use WDS.
- The . WRT54G also supports WDS as an undocumented feature, {Link without Title} .
- All is installed.
- Some Buffalo routers support WDS, all of the Nfniti routers plus the WHR-HP-AG108 does NOT support WDS.
- All NETGEAR ProSafe access points (WG102, WAG102, WG302, WAG302) natively support the full implementation of the Wireless Distribution System. Several of their SOHO devices do also, whether with full implementations like the WG602v2/v3 or partial implementations like the WPN802.
- All U.S. Robotics MAXg wireless products (5451, 5461, 9108, 5432, 5441) support WDS.
- MSI's RG54SE and probably other routers support WDS, while providing both wireless and ethernet connection to the router.
- Zoom X6 (Firmware Version 2.0.4) supports WDS
- Siemens Gigaset SE551 WLAN supports WDS.
- CNet Wireless-G MIMO Router (CWR-903)
- SMC EZ Connect G Wireless Access Point (SMCWEBT-G), SMC7908VoWBRA support WDS.
- Edimax Access Point EW-7206APg and Router Broadband BR-6304WG support WDS
- E-Tech WGRT04, WGRT05, WMRT01, ADWG05, ADWG06 support WDS.
- Eminent EM4032, EM4114, EM4115, EM4030, EM4040, EM4050, EM4214, 4216 support WDS
- Thomson's SpeedTouch 780 WL & 585 support WDSs
- D-link DGL-4300 (Firmware 1.8+)
- Draytek 2700, 2800 series routers and some 2600 series (Wireless hardware v2) support WDS.
- Canyon CN-WF514M MIMO Wireless Broadband Router supports WDS
- 3COM OfficeConnect ADSL Wireless 11g Firewall Router Version 1.00.00.T13 supports WDS
- 3Com Wireless 7760 11a/b/g PoE Access Point supports WDS
- HP ProCurve AP 530
- Allied Telesis AT-WA7400, AT-WA1104G, AT-WR4561 & AT-WR4562 are supporting WDS
- Alcatel SpeedTouch 716 supports WDS
- Some ValuePoint products including the 700g MultiSSID AP support WDS, sometimes with a firmware upgrade.
: Wireless Distribution System is distinct from the WDS implementation by Cisco, which stands for Wireless Domain Services .
WDS can be used to provide two modes of wireless AP-to-AP connectivity:
- Wireless Bridging in which WDS APs communicate only with each other and don't allow wireless clients or Stations (STA) to access them
- Wireless Repeating in which APs communicate with each other and with wireless STAs
Two disadvantages to using WDS are:
- Wireless throughput is cut approximately in half for each WDS repeating "hop", i.e. an AP that data flows through before hitting the wired network. This is because all transmissions use the same channel and radio and must be retransmitted to reach the wired LAN.
- Dynamically assigned and rotated encryption keys are usually not supported in a WDS connection. This means that dynamic Wi-Fi Protected Access (WPA) and other dynamic key assignment technology in most cases can not be used, though WPA using pre-shared keys is possible. This is due to the lack of regulation in this field, which will hopefully be resolved with the upcoming 802.11s standard. As a result only static WEP or WPA keys may be used in a WDS connection, including any STAs that associate to a WDS repeating AP.
Most third party firmwares for the WRT54G(S)/GL support AES encryption using WPA2-PSK Mixed Mode security, and TKIP encryption using WPA-PSK, while operating in WDS mode. However, this mode may not be compatible with other units running stock or alternate firmwares.
|
