User's Manual

Wireless Array
348 Configuring the Wireless Array
Procedure for Setting Up WDS Client Links
WDS Client Link Settings:
1. Host Link Stations: Check the Allow checkbox to instruct the Array to
allow stations to associate to IAPs on a host Array that participates in a
WDS link. The WDS host IAP will send beacons announcing its
availability to wireless clients. This is disabled by default.
2. Spanning Tree Protocol (STP): Check the Enable checkbox to instruct the
Array to enforce the Spanning Tree Protocol on all WDS links. This is
enabled by default. Use of STP is strongly recommended in most
situations. However, in situations like the one in the next step, where
WDS is used by an Array mounted on a high speed train, STP can add
significant delay (often on the order of 30 to 60 seconds) while initially
analyzing network topology. In such a situation, it may be desirable to
disable STP.
3. Roaming RSSI Threshold: If an Array is deployed on a mobile site (on a
train, for example), you can use WDS to implement a wireless backhaul
that will roam between Arrays at fixed locations. When another
candidate Array for WDS host target is found, the client link will roam to
the new Array if its RSSI is stronger than the RSSI of the current host
connection by at least the Roaming RSSI Threshold. The default is 6 dB.
4. Roaming RSSI Averaging Weight: This weight changes how much the
latest RSSI reading influences the cumulative weighted RSSI value
utilized in checking the threshold (above) to make a roaming decision.
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Once an IAP has been selected to act as a WDS client link, no other
association will be allowed on that IAP. However, wireless associations will
be allowed on the WDS host side of the WDS session.
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Caution: If STP is disabled and a network connection is made on the WDS
Client Array’s Gigabit link that can reach the WDS Host Array, broadcast
and multicast packets will not be blocked. A broadcast storm may cause a
network outage.