Nortel 120, Инструкция по использованию

Страница: 85 / 130

WebUI navigation 85
If the RTS threshold is set to 0, the access point always sends RTS signals.
If set to 2 347, the access point never sends RTS signals. If set to any
other value, and the packet size equals or exceeds the RTS threshold, the
RTS/CTS (Request to Send / Clear to Send) mechanism is enabled.
The access points contending for the medium may not be aware of each
other. The RTS/CTS mechanism can solve this Hidden Node Problem.
(Range: 0-2 347 bytes: Default: 2 347 bytes)
Configuring Wi-Fi multimedia
Wireless networks offer an equal opportunity for all devices to transmit
data from any type of application. Although this is acceptable for most
applications, multimedia applications (with audio and video) are particularly
sensitive to the delay and throughput variations that result from this equal
opportunity wireless access method. For multimedia applications to run well
over a wireless network, a Quality of Service (QoS) mechanism is required
to prioritize traffic types and provide an enhanced opportunity wireless
access method.
The access point implements QoS using the Wi-Fi Multimedia (WMM)
standard. Using WMM, the access point is able to prioritize traffic and
optimize performance when multiple applications compete for wireless
network bandwidth at the same time. WMM employs techniques that are a
subset of the developing IEEE 802.11e QoS standard and it enables the
access point to inter operate with both WMM- enabled clients and other
devices that may lack any WMM functionality.
Access categories — WMM defines four access categories (ACs): voice,
video, best effort, and background. These categories correspond to traffic
priority levels and are mapped to IEEE 802.1D priority tags (see
"WMM
Access Categories" (page 85) ). The direct mapping of the four ACs to
802.1D priorities is specifically intended to facilitate inter operability with
other wired network QoS policies. While the four ACs are specified for
specific types of traffic, WMM allows the priority levels to be configured to
match any network-wide QoS policy. WMM also specifies a protocol that
access points can use to communicate the configured traffic priority levels
to QoS-enabled wireless clients.
WMM Access Categories
WMM Access Categories
Access Category
WMM Designation Description 802.1D Tags
AC_VO (AC3) Voice Highest priority,
minimum delay.
Time-sensitive data
such as VoIP (Voice
over IP) calls. 7, 6
BAP120
Using the Nortel Business Access Point 120
NN47921-301 01.01 Standard
1.0 August 2006
Copyright © 2006, Nortel Networks Nortel Networks Confidential
.