ZyXEL Communications MWR102, Руководство пользователя

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If the Fragmentation Threshold value is smaller than the RTS/CTS value (see previously) you
set then the RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as data
frames will be fragmented before they reach
RTS/CTS size.
Preamble Type
A preamble is used to synchronize the transmission timing in your wireless network. There are
two preamble modes:
Long and Short .
Short preamble takes less time to process and minimizes overhead, so it should be used in a
good wireless network environment when all wireless stations support it.
Select Long if you have a ‘noisy’ network or are unsure of what preamble mode your wireless
stations support as all IEEE 802.11b compliant wireless adapters must support long preamble.
However, not all wireless adapters support short preamble. Use long preamble if you are unsure
what preamble mode the wireless adapters support, to ensure interpretability between the AP and
the wireless stations and to provide more reliable communication in ‘noisy’ networks.
Select Dynamic to have the AP automatically use short preamble when all wireless stations
support it, otherwise the AP uses long preamble.
Note: The AP and the wireless stations MUST use the same preamble mode in order to
communicate.
IEEE 802.11g Wireless LAN
IEEE 802.11g is fully compatible with the IEEE 802.11b standard. This means an IEEE 802.11b
adapter can interface directly with an IEEE 802.11g access point (and vice versa) at 11 Mbps or
lower depending on range. IEEE 802.11g has several intermediate rate steps between the
maximum and minimum data rates. The IEEE 802.11g data rate and modulation are as follows: