User Manual Part 2

Wireless Nd1 Router User Guide
Request to Send/Clear to Send (RTS/CTS) channel contention mechanism is used. In
a network with significant radio interference or large number of wireless devices on
the same channel, reducing the RTS Threshold might help in reducing frame loss. The
RTS threshold is 2347 bytes by default, which is the maximum value.
● Fragmentation threshold: The maximum level the router will reach when sending
information in packets before the packets are broken up in fragments. Typically, if you
are experiencing problems sending information, it is because there is other traffic on
the network and the data being transmitted is colliding. This might be corrected by
the information being broken into fragments. The lower the level that the
Fragmentation threshold is set to, the smaller a packet has to be before it is broken
into fragments. If the maximum is set (2346), fragmentation is essentially disabled.
You should only change this level if you are an advanced user.
● DTIM Interval: This parameter configures the amount of time after which buffered
broadcast and multicast frames will be delivered to the wireless clients. This allows
mobile stations to conserve power. If you are using applications which use broadcast
or multicast frames for delivering data, you should use a Delivery Traffic Indication
Message (DTIM) Interval of 1 to minimize delay for real-time traffic, such as multicast
audio and video streams.
● Preamble: Defines the length of the Cyclic Redundancy Check (CRC) block for
communication between the router and wireless clients. The preamble consists of the
Synchronization and Start Frame Delimiter (SFD) fields. The sync field is used to
indicate the delivery of a frame to wireless stations, to measure frequency of the radio
signal, to perform corrections if needed. The SFD at the end of the Preamble is used
to mark the start of the frame.
If you are not using any 802.11b devices in your network, you can configure the
Preamble type to Short for optimum performance. The Long Preamble type should be
used when both 802.11g and 802.11b devices exist on your network.
Note: Click Save to apply all your new settings and reboot the router after you have
completed all your changes.
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