HP ProCurve 520wl Wireless Access Point - Manual (Page 51)

Advanced Configuration
Wireless (802.11a)
You can configure and view the following parameters within the Wireless Interface Configuration screen for an
802.11a AP:
NOTE
You must reboot the Access Point before any changes to these parameters take effect.
• Physical Interface Type: For an 802.11a AP, this field reports: “802.11a (OFDM 5 GHz).” OFDM stands for
Orthogonal Frequency Division Multiplexing; this is the name for the radio technology used by 802.11a devices.
• MAC Address: This is a read-only field that displays the unique MAC (Media Access Control) address for the
Access Point’s wireless interface. The MAC address is assigned at the factory.
• Regulatory Domain: Reports the regulatory domain for which the AP is certified. Not all features or channels are
available in all countries. The available regulatory domains include:
— FCC - U.S./Canada, Mexico, and Australia
— ETSI - Europe and the United Kingdom
— MKK: Japan
— SG: Singapore
— ASIA: China, Hong Kong, and South Korea
— TW: Taiwan
• Network Name (SSID): Enter a Network Name (between 2 and 31 characters long) for the wireless network. You
must configure each wireless client to use this name as well.
• Auto Channel Select: The AP scans the area for other Access Points and selects a free or relatively unused
communication channel. This helps prevent interference problems and increases network performance. By default
this feature is enabled. See
802.11a Channel Frequencies for a list of Channels.
NOTE
You cannot disable Auto Channel Select for 802.11a products in Europe (see Dynamic Frequency Selection
(DFS) for details).
• Frequency Channel: When Auto Channel Select is enabled, this field is read-only and displays the Access Point’s
current operating Channel. When Auto Channel Select is disabled, you can specify the Access Point’s channel. If
you decide to manually set the unit’s Channel, ensure that nearby devices do not use the same frequency.
Available Channels vary based on regulatory domain. See
802.11a Channel Frequencies . Note that you cannot
manually set the channel for 802.11a products in Europe (see Dynamic Frequency Selection (DFS) for details).
• Transmit Rate: Use the drop-down menu to select a specific transmit rate for the AP. Choose between 6, 9, 12,
18, 24, 36, 48, 54 Mbits/s, and Auto Fallback. Auto Fallback is the default setting; it allows the AP unit to select the
best transmit rate based on the cell size.
• DTIM Period: The Deferred Traffic Indicator Map (DTIM) is used with clients that have power management
enabled. DTIM should be left at 1, the default value, if any clients have power management enabled. This
parameter supports a range between 1 and 255.
• RTS/CTS Medium Reservation: This parameter affects message flow control and should not be changed under
normal circumstances. Range is 0 to 2347. When set to a value between 0 and 2347, the Access Point uses the
RTS/CTS mechanism for packets that are the specified size or greater. When set to 2347 (the default setting),
RTS/CTS is disabled. See
RTS/CTS Medium Reservation for more information.
• Closed System: Check this box to allow only clients configured with the Access Point’s specific Network Name to
associate with the Access Point. When enabled, a client configured with the Network Name “ANY” cannot connect
to the AP. This option is disabled by default.
Dynamic Frequency Selection (DFS)
802.11a APs sold in Europe use a technique called Dynamic Frequency Selection (DFS) to automatically select an
operating channel. During boot-up, the AP scans the available frequency and selects a channel that is free of
interference. If the AP subsequently detects interference on its channel, it automatically reboots and selects another
channel that is free of interference.
DFS only applies to 802.11a APs used in Europe (i.e., units 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.
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