SIMREX DataMover ESS, User Manual

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60 DataMover ESS User’s Guide SIMREX MAN.ESS-01, Rev. F
SIMREX Corporation
Invisible place holder
Figure 3-24. Radio Configuration Menu—Remote
Other parameter settings that should be reviewed for Mobility Mode:
•
Compression
[
AP; disabled
]—Disable radio compression. Data
compression is best performed by the middleware running on
the mobile laptop PC. Gains in efficiency are made because
middleware compresses data at a higher stack level, and it
aggregates multiple data frames and streams into a single
packet. Compression at the radio level, although highly effi-
cient, works at the individual packet level.
•
Dwell Time
[
Set to the minimum value
]—This setting controls the
amount of time that the unit spends on each frequency between
hops. Although overall throughput appears to decrease by this
setting the effects of multipath fading are minimized through
frequency diversity.
•
Beacon Period
[
Set to the fastest value
]—This parameter defines
the interval at which the Access Point transmits a synchroniza-
tion beacon to all remotes. A faster setting minimizes resyn-
chronization times when remote radios roam between access
points or in highly interrupted coverage areas (dense buildings,
for example).
•
Fragmentation Threshold
[
remote; 256
]—Set to a small value. This
parameter defines the size of the message packets transmitted
over the wireless media. These fragments are reconstructed into
the original packet before delivery to the external device at the
remote end of the link. In a mobile environment with rapidly
changing conditions, setting this value to a minimum value
improves the probability of packets being sent complete on the
first try.