Hawking HPOW5CM, Руководство пользователя

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which support power saving mode, when to wake up to receive multicast frame.
DTIM is necessary and critical in wireless environment as a mechanism to fulfill
power-saving synchronization.
A DTIM interval is a count of the number of beacon frames that must occur
before the access point sends the buffered multicast frames. For instance, if
DTIM Interval is set to 3, then the Wi-Fi clients will expect to receive a multicast
frame after receiving three Beacon frame. The higher DTIM interval will help
power saving and possibly decrease wireless throughput in multicast
applications.
Fragment Threshold: Set the fragment threshold of the wireless radio. The default value is 2346.
RTS Threshold: RTS Threshold is in the range of 1~2347 byte. The default is 2347 byte. The main
purpose of enabling RTS by changing RTS threshold is to reduce possible
collisions due to hidden wireless clients. RTS in AP will be enabled automatically
if the packet size is larger than the Threshold value. By default, RTS is disabled in
a normal environment supports non-jumbo frames.
Short Preamble: By default, its set to “Enabled”. If Disabled, the device will use Long 128-bit
Preamble Synchronization field. The preamble is used to signal "here is a train of
data coming" to the receiver. The short preamble provides 72-bit
Synchronization field to improve WLAN transmission efficiency with less
overhead.
IGMP Snooping: The process of listening to Internet Group Management Protocol (IGMP)
network traffic. The feature allows a network switch to listen in on the IGMP
conversation between hosts and routers. By listening to these conversations the
switch maintains a map of which links need which IP multicast streams.
Multicasts may be filtered from the links which do not need them and thus
controls which ports receive specific multicast traffic.
Greenfield: In wireless WLAN technology, greenfield mode is a feature of major components
of the 802.11n specification. The greenfield mode feature is designed to improve
efficiency by eliminating support for 802.11b/g devices in an all draft-n network.
In greenfield mode the network can be set to ignore all earlier standards.
5-3 WMM QoS
This affects traffic flowing from the access point to the client station. Configuring QoS options consists of
setting parameters on existing queues for different types of wireless traffic. You can configure different
minimum and maximum wait times for the transmission of packets in each queue based on the
requirements of the media being sent. Queues automatically provide minimum transmission delay for
Voice, Video, multimedia, and mission critical applications, and rely on best-effort parameters for
traditional IP data.