Evolve WR150N, User Manual

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than the threshold, the RTS/CTS handshake gets triggered. If the packet size is equal to or less than
threshold the data frame gets sent immediately.
System uses Request to Send/Clear to send frames for the handshake that provide collision
reduction for an access point with hidden stations. The stations are sending a RTS frame first
while data is sent only after a handshake with an AP is completed. Stations respond with the
CTS frame to the RTS, which provide clear media for the requesting station to send the data.
CTS collision control management has a time interval defined during which all the other stations
hold off the transmission and wait until the requesting station will finish transmission.
TX Power: display the data transmission rate power.
Short Preamble: this option is to define the length of the sync field in an 802.11 packet. Most
modern wireless network uses shot preamble with 56 bit sync filed. By default, it is disabled.
Short Slot: by default, this is enabled.
Tx Burst: enable this function will make it easy for you to enhance the performance in data
transmission.
Pkt_Aggregate: by default, this is disabled.
20/40 BssCoexSupport: by default, it is enabled. Support 20/40 at the same time.
IGMP Snooping: if you enable this function, multicast traffic will be forwarded to ports that have
members of that group. Disabling IGMP snooping will make multicast traffic treated in the same
manner as broadcast traffic.
WMM Capable: by default, it is disabled.
WMM is an abbreviation of Wi-Fi Multimedia. It defines the priority levels for four access categories
derived from 802.1d (prioritization tabs). The categories are designed with specific types of traffic,
voice, video, best effort and low priority data.
5.4 Firewall
While the broadband users demand more bandwidth for multimedia, interactive applications, or
distance learning, security has been always the most concerned. The firewall of this router helps to
protect you local network against attack from unauthorized outsiders. It also restricts users in the
local network from accessing the Internet. Furthermore, it can filter out specific packets that
trigger the router to build an unwanted outgoing connection.