User's Manual

428 | Virtual APs Dell Networking W-Series ArubaOS 6.4.x| User Guide
Parameter Description
Short guard interval in 40 MHz
mode
Enable or disable use of short (400ns) guard interval in 40 MHz mode. This
parameter is enabled by default.
A guard interval is a period of time between transmissions that allows
reflections from the previous data transmission to settle before an AP
transmits data again. An AP identifies any signal content received inside
this interval as unwanted inter-symbol interference, and rejects that data.
The 802.11n standard specifies two guard intervals: 400ns (short) and
800ns (long). Enabling a short guard interval can decrease network
overhead by reducing unnecessary idle time on each AP. Some outdoor
deployments, may, however require a longer guard interval. If the short
guard interval does not allow enough time for reflections to settle in your
mesh deployment, inter-symbol interference values may increase and
degrade throughput.
Supported MCS set A list of Modulation Coding Scheme (MCS) values or ranges of values to be
supported on this SSID. The MCS you choose determines the channel
width (20MHz vs. 40MHz) and the number of spatial streams used by the
mesh node.
The default value is 1–23; the complete set of supported values. To specify
a smaller range of values, enter a hyphen between the lower and upper
values. To specify a series of different values, separate each value with a
comma.
Examples:
2–10
1,3,6,9,12
Range: 0–23.
Temporal Diversity
When this feature is enabled and the client is not responding to 802.11
packets, the AP will launch two hardware retries; if the hardware retries
are not successful then it attempts software retries. This setting is dis-
abled by default.
In order for the settings in this profile to take effect, the profile must be associated with an AP's Virtual AP
profile. For details on associating a high-throughput SSID profile with a Virtual APprofile, see Configuring the
Virtual AP Profile on page 396
In the CLI
(host)(config) wlan ht-ssid-profile <profile-name>
(host)(config) wlan ssid-profile <profile-name>
ht-ssid-profile <profile>
(host)(config) wlan virtual-ap <profile-name>
hwlan ssid-profile <profile-name>
Guest WLANs
Guest usage in enterprise wireless networks requires the following special consideration:
l Guest users must be separated from employee users by VLANs in the network.
l Guests must be limited not only in where they may go, but also by what network protocols and ports they
may use to access resources.
l Guests should be allowed to access only the local resources that are required for IP connectivity. These
resources include DHCP and possibly DNS if an outside DNS server is not available. In most cases, a public
DNS is always available.