User's Manual

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What is IPSEC?
IPSEC is the abbreviation
of IP Security. It is used to transferring data securely under VPN.
What is WLAN
Block Relay Between Clients?
An Infrastruct
ure Basic Service Set is a BSS with a component called an Access Point (AP). The access point
provides a local relay function for the BSS. All stations in the BSS communicate with the access point and no longer
communi
cate directly. All frames are relayed between stations by the access point. This local relay function effectively
doubles the range of the IBSS.
What is WMM?
WMM is b
ased on a subset of the IEEE 802.11
e WLAN QoS draft standard. WMM adds prioritized capabilities to
Wi-Fi networks and optimizes their performance when multiple concurring applications, each with different latency and
throughput requirements, compete for network resources. By using WMM, end-user satisfaction is maintained in a
wider variety of environments and traffic conditions. WMM makes it possible for home network users and enterprise
network managers to decide which data streams are most important and assign them a higher traffic priority.
What is WLAN ACK TIMEOUT?
ACK frame h
as to receive ACK timeout frame. If remote does
not receive in specified period, it will be retransmitted.
What is Modulation Coding Scheme (MCS)?
MCS is Wi
reless link data rate for 80
2.11n. The throughput/range performance of a AP will depend on its
implementation of coding schemes. MCS includes variables such as the number of spatial streams, modulation, and
the data rate on each stream. Radios establishing and maintaining a link must automatically negotiate the optimum
MCS based on channel conditions and then continuously adjust the selection of MCS as conditions change due to
interference, motion, fading, and other events.
What is Frame Aggregation?
Every 802.11
packet, no matter how small, has a fixed amount of overhe
ad associated with it. Frame Aggregation
combines multiple smaller packets together to form one larger packet. The larger packet can be sent without the
overhead of the individual packets. This technique helps improve the efficiency of the 802.11n radio allowing more
end user data to be sent in a given time.
What is Guard Intervals (GI)?
A GI is a peri
od of time between symbol transmissio
n that allows reflections (from multipath) from the previous data
transmission to settle before transmitting a new symbol. The 802.11n draft specifies two guard intervals: 400ns (short)
and 800ns (long). Support of the 400ns GI is optional for transmit and receive. The purpose of a guard interval is to
introduce immunity to propagation delays, echoes, and reflections to which digital data is normally very sensitive.