ZyXEL P-660HN-51 User Guide - Page 295

Fragmentation Threshold, Preamble Type, IEEE 802.11g Wireless LAN

Page 295 highlights

Appendix D Wireless LANs Fragmentation Threshold A Fragmentation Threshold is the maximum data fragment size (between 256 and 2432 bytes) that can be sent in the wireless network before the AP will fragment the packet into smaller data frames. A large Fragmentation Threshold is recommended for networks not prone to interference while you should set a smaller threshold for busy networks or networks that are prone to interference. 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 Preamble is used to signal that data is coming to the receiver. Short and long refer to the length of the synchronization field in a packet. Short preamble increases performance as less time sending preamble means more time for sending data. All IEEE 802.11 compliant wireless adapters support long preamble, but not all support short preamble. Use long preamble if you are unsure what preamble mode other wireless devices on the network support, and to provide more reliable communications in busy wireless networks. Use short preamble if you are sure all wireless devices on the network support it, and to provide more efficient communications. Use the dynamic setting to automatically use short preamble when all wireless devices on the network support it, otherwise the ZyXEL Device uses long preamble. Note: The wireless devices 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 P-660HN-TxA User's Guide 295

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Appendix D Wireless LANs
P-660HN-TxA User’s Guide
295
Fragmentation Threshold
A
Fragmentation Threshold
is the maximum data fragment size (between 256
and 2432 bytes) that can be sent in the wireless network before the AP will
fragment the packet into smaller data frames.
A large
Fragmentation Threshold
is recommended for networks not prone to
interference while you should set a smaller threshold for busy networks or
networks that are prone to interference.
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
Preamble is used to signal that data is coming to the receiver. Short and long refer
to the length of the synchronization field in a packet.
Short preamble increases performance as less time sending preamble means
more time for sending data. All IEEE 802.11 compliant wireless adapters support
long preamble, but not all support short preamble.
Use long preamble if you are unsure what preamble mode other wireless devices
on the network support, and to provide more reliable communications in busy
wireless networks.
Use short preamble if you are sure all wireless devices on the network support it,
and to provide more efficient communications.
Use the dynamic setting to automatically use short preamble when all wireless
devices on the network support it, otherwise the ZyXEL Device uses long
preamble.
Note: The wireless devices 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