Compaq WL110, Руководство пользователя

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6-6 Optimizing Performance
grouped into the same LAN segment. 11Mbps Wireless LAN stations
will not be able to roam between LAN segments that are separated by
routers and/or gateways.
If this does not solve your problem, consider one of the following options as
described in this chapter:
■
Protocol Filtering (page 6-2)
■
Optimizing Wireless Connections (page 6-6)
Optimizing Wireless Connections
When the link quality of communications between a wireless station and its
Access Point is poor, packets communicated between this station and the Access
Point may get lost. Waiting in vain for an acknowledgment of the receiving
station, the sending station will re-transmit the lost packet.
Upon receipt of the same packet for the second time, the receiving station might
decide to discard all packets received so-far, which would require that the
sending station will have to retransmit all packets once again.
Please note that:
■
Many retransmissions may affect your effective data throughput efficiency
as the “true data” has to share the wireless bandwidth with the re-
transmitted frames.
■
The retransmissions will also degrade the performance as perceived by the
end-user of a wireless stations: e.g. saving a file will take longer if many
retransmissions are required.
A poor link quality can be caused by one or more of the following problems:
■
The station is almost out of range of the Access Point.
■
There is a source of interference in the signal path between the station and
the Access Point.
■
A station may be “hidden” from another station within the same coverage
area (for more information on hidden stations, see the section “RTS/CTS
Medium Reservation” on page 6-9).
Diagnosing Link Quality
The occurrence of a poor link quality on the wireless network can be diagnosed
in different ways.
■
You can use the A PManager tool to diagnose the quality of radio
communications on-site as described in chapter 5“Monitoring your
11Mbps Wireless LAN Network”, or
■
Use the AP Manager tool to investigate from your current location whether
a specific remote area is suffering from poor radio performance.
The AP Manager provides the following options to diagnose radio link
quality:
— The remote link test