HP ProCurve 520wl Wireless Access Point - Manual (Page 29)

Change your Wireless Interface Settings
2-16
enabling acs enabling acs enabling acs enabling acs
1. From the Web interface, select Configuration Configuration Configuration Configuration then click the Interfaces Interfaces Interfaces Interfaces tab.
2. Select the check box to Enable Auto Channel Select Enable Auto Channel Select Enable Auto Channel Select Enable Auto Channel Select .
CAUTION: !
On changing the status you must reboot your WL520, which will disconnect all clients from the WL520.
dynamic frequency selection (dfs) dynamic frequency selection (dfs) dynamic frequency selection (dfs) dynamic frequency selection (dfs)
802.11a cards sold in Europe use a technique called Dynamic Frequency Selection (DFS) to automatically select an operating
channel. During boot-up, the WL520 scans the available frequency and selects a channel that is free of interference. If the
WL520 subsequently detects interference on its channel, it automatically reboots and selects another channel that is free of
interference.
DFS only applies to 802.11a cards used in Europe (i.e., cards whose regulatory domain is set to ETSI). The European
Telecommunications Standard Institute (ETSI) requires that 802.11a devices use DFS to prevent interference with radar systems
and other devices that already occupy the 5 GHz band.
If you are using 802.11a cards in Europe, keep in mind the following:
Q
DFS is not a configurable parameter. It is always enabled and cannot be disabled.
Q
You cannot manually select an operating channel for 802.11a cards; you must let DFS select the channel.
Q
You cannot configure the Enable Auto Channel Select Enable Auto Channel Select Enable Auto Channel Select Enable Auto Channel Select option. Within the HTTP interface, this option will always appear
enabled.
Q
802.11b cards (and 802.11a cards outside of Europe) use ACS (which can be enabled or disabled, see Auto
Channel Select (ACS) for details).
distance between aps distance between aps distance between aps distance between aps
NOTE:
This feature is only applicable to 2.4 GHz (802.11b) cards.
cells cells cells cells
Distance Between APs defines how far apart (physically) your WL520 devices are located, which in turn determines the size of
your cell. Cells of different sizes have different capacities and therefore suit different applications. For instance, a typical office
has many stations requiring high bandwidth and transmit rates for complex, high-speed data processing. In contrast, a typical
warehouse has a few forklifts requiring low bandwidth and transmit rates for simple transactions.
Cell capacities are compared in the following table, which shows small cells suit most offices, while large cells suit most
warehouses:
small cell small cell small cell small cell large cell large cell large cell large cell
Physically accommodates few stations Physically accommodates many stations
High cell bandwidth per station Lower cell bandwidth per station
High transmit rate Lower transmit rate