User's Manual

Fortress ES-Series CLI Guide: Networking and Radio Configuration
47
RadioBand[802.11g](802.11b|802.11g|802.11nght20|802.11nght40plus|802.11nght40minus|
802.11a|802.11naht20|802.11naht40plus|802.11naht40minus to set band):
ShortPreamble[enable] (enable|disable to set 802.11b short preamble):
[...etc.]
The short preamble is used by virtually all wireless devices
currently being produced, so leaving the setting at its default
enabled value is recommended for most network deployments.
When
ShortPreamble is disabled, connecting devices must
use the long preamble, which is still in use by some older
802.11b devices. If the WLAN must support devices that use
the long preamble, you must
disable ShortPreamble.
802.11n Options
BSSs configured on the radio(s) installed in certain Mesh Point
models are additionally capable of 802.11n operation (refer to
Table 3.1 on page 38).
A Mesh Point radio BSS configured to use the 802.11n standard
is
fully interoperable with other 802.11n network devices.
On 802.11n-capable radios, there are three possible high-
throughput
( ht ) 802.11n options for each frequency band
supported on the radio: three for the 5 GHz
802.11na band
and three for the 2.4 GHz
802.11ng band, when present:
 ht20 - 802.11n - High-Throughput 20 MHz, the radio will
use only 20 MHz channel widths, while taking advantage of
the standard’s traffic handling efficiencies.
 ht40plus - High-Throughput 40 MHz plus 20 MHz, the
radio can use 40 MHz channel widths by binding the
selected 20 MHz channel to the adjacent 20 MHz channel
above it on the radio spectrum.
 ht40minus - High-Throughput 40 MHz minus 20 MHz, the
radio can use 40 MHz channel widths by binding the
selected 20 MHz channel to the adjacent 20 MHz channel
below it on the radio spectrum.
On ES2440-34m and ES2440-3444m Mesh Points, there is a
fourth high-throughput (
ht) option for the 4.4 GHz band radios:
 ht10 - 802.11na - High-Throughput 10 MHz, the radio will
use only 10 MHz channel widths while taking advantage of
the standard’s traffic handling efficiencies.
NOTE: Changing
the radio
guard-
interval
requires you
to reboot the Mesh Point
(see Section 5.2).
When an 802.11n HT40 band setting is specified
(
802.11naht40plus, 802.11naht40minus,
802.11nght40plus, and 802.11nght40minus), you can
specify whether the radio will use only
long guard intervals
between symbol transmissions (the default), or that the radio
can use
any (i.e., both long and short) symbol transmission
guard intervals.