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Link Name (SSID or ESSID)
– The link name is the link ID. All bridge units that
are connected together need to have exact the same name. This name can be
considered the general link name.
Encrypt link using AirLock™ security
– This option allows you to switch the
security on or off. It is advised to have AirLock™ always switched on. Airlock™
provides you superior security and protects you against eavesdrops, hacking,
etc.
Contention window
– This is the back-off window expressed in slot time. 1
means 1slot time, which equals 20 microseconds. This parameter may need to
be manipulated when the traffic is out of balance or if the link is set to point-to-
multipoint. Out of balance means more data upstream then downstream, or vice
versa. Having the diversity option selected within the antenna field will also
creates some extra requirements for the contention window. Diversity makes the
radio listen to both antennas. This does not happen at the same time; it will
constantly switch between the two antennas. So it will listen 1 slot time to
antenna 1 and the next slot time to antenna 2. Use medium and high when the
traffic is out of balance or in a point to multipoint. Short will work on standard
point to point links.
ACK window
, – This is the waiting time for the acknowledgement. Select the
setting that corresponds with the length of the actual link. For a point to multipoint
situation use the longest link as a reference. It will not harm the link if the ACK
window is larger than the corresponding distance. To fine tune the throughput,
increase the number, measure the throughput, and then start to decrease the
ACK window while monitoring the throughput.
Short retry limit
– The short retry limit sets the number of retries for packets
smaller than the number defined in the RTS/CTS threshold field.
RTS/CTS threshold
– Packages longer than this value will be transmitted via
‘request to send/ clear to send’ routine. This method of transmitting provides an
extremely secure and reliable link, but will slow it down significantally. Since the
reliability of the link without RTS/CTS communication is already outstanding it is
advised to use this option only in complex and hostile environments.
Long retry limit
– The long retry limit sets the number of retries for packets
longer than the number defined in the RTS/CTS threshold field.
Fragmentation threshold
– This value sets the threshold where above which
the packets will be fragmented.
