Advanced Configuration AP-700 User Guide
Interfaces
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NOTE: Turbo mode is supported in only in 802.11a mode in the FCC regulatory domain when DFS is not required.
If turbo mode is enabled, then this is displayed in the web UI and the transmit speeds and channels
pull-down menus are updated with the valid values.
• DTIM Period: The Deferred Traffic Indicator Map (DTIM) Period determines when to transmit broadcast and multicast
packets to all clients. If any clients are in power save mode, packets are sent at the end of the DTIM period. This
parameter supports a range between 1 and 255; it is recommended to leave the DTIM at its default value unless
instructed by technical support. Higher values conserve client battery life at the expense of network performance for
broadcast or multicast traffic.
• 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.
• Antenna Gain: This parameter modifies the sensitivity of the radio card when detecting radar signals in accordance
with Dynamic Frequency Selection/Radar Detection (DFS/RD) requirements. Given that the radar detection threshold
is fixed by the regulatory codes in the country of operation, and that a variety of antennas with different gains may be
attached to the unit, adjust this threshold to account for higher than expected antenna gains and avoid false radar
detection events. Set this parameter to a value between 0 and 35. The default value is 0.
• Wireless Service Status: Select Shutdown to shutdown the wireless service on a wireless interface, or to Resume
to resume wireless service. See Wireless Service Status for more information.
• Load Balancing Max Clients: Load balancing distributes clients among available access points. Enter a number
between 1 and 63 to specify the maximum number of clients to allow.
• Channel Blacklist Table: The Channel Blacklist table contains all available channels. It can be used to manually
blacklist channels, and it also reflects channels that have been automatically blacklisted by the Dynamic Frequency
Selection/Radar Detection (DFS/RD) function. See Channel Blacklist Table for configuration information.
• Wireless Distribution System: A Wireless Distribution system can be used to establish point-to-point (i.e. wireless
backhaul) connections with other access points. See Wireless Distribution System (WDS) for configuration
information.
Dynamic Frequency Selection/Radar Detection (DFS/RD)
In order to prevent interference with radar systems and other devices that occupy the 5 GHz band, 802.11a APs certified
in the ETSI, TELEC, FCC, and IC regulatory domains (see Affected Countries) and operating in the middle and high
frequency bands select an operating channel through a combination of Auto Channel Select (ACS) and Dynamic
Frequency Selection (DFS)/Radar Detection (RD).
During boot-up, ACS scans the available channels and selects the best channel. Once a channel is selected, the AP
performs a channel availability check for 60 seconds to ensure that the channel is not busy or occupied by radar, and
then commences normal operation. (In Canada, if the channel was previously blacklisted, the AP scans for 600 seconds
before commencing normal operation if the selected channel frequency is in the 5600 - 5650 MHz range). When the AP
enters normal operation, DFS works in the background to detect interference in that channel. If interference is detected,
the AP sends a trap, disassociates all clients, blacklists the channel, and reboots. After it reboots, ACS re-scans and
selects a better channel that is not busy and is free of radar interference.
If ACS is disabled, only channels in the lower, upper, and ISM frequency bands are available for use:
• 36: 5.180 GHz (default)
• 40: 5.200 GHz
• 44: 5.220 GHz
• 48: 5.240 GHz
• 149: 5.745 GHz
• 153: 5.765 GHz
• 157: 5.785 GHz
