US Robotics USR5454 User Manual page 52

Wireless Nd1 Router User Guide
Beacon Interval: The amount of time between beacon transmissions. A beacon is
basically a heartbeat for a wireless client or access point, sending out a signal
informing the network that it is still active. This should be set between 1 and 1000
milliseconds. The default beacon interval is 100 ms.
RTS threshold: The RTS Threshold is the minimum size in bytes for which the
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 access point 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 access point 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 access point after
you have completed all your changes.
file:///G|/CSO/Documentation/Documentation%20-%20D...4%20Mach-1%20AP/User%20Guide/English/wireless.html (16 of 17)10/26/2006 9:47:10 AM