Instruction manual

2-88
BreezeACCESS Version 4.3 Operations and Administration
Manual Revision: 4.0
degradation has been incorporated into the AU, ensuring that the
degradation of performance for each individual subscriber will be
proportional to its CIR.
The MIR/CIR algorithm uses buffers to control the flow of data. To
average the performance over time, a special Burst Duration
algorithm is employed to enable higher transmission rates after a
period of inactivity. If no data was received from the Ethernet port
during the last N seconds, the unit is allowed to transmit N times its
CIR value without any delay. For example, after an inactivity time of
0.5 second, a unit with CIR = 64 Kbps can transmit up to 64 Kbits x
0.5 = 32 Kbits without any delay.
 MIR/CIR Option – Enables or disables the CIR/MIR support
feature. In cells where the AU and all SUs use SW version 4.0
and higher, the MIR/CIR Option in the AU controls the
operation of the whole cell. The MIR/CIR Option in the SU is
thus meaningless, as the setting of the option in the AU will
override possible conflicting setting in any of the served SUs.
The option is available in the SUs only for compatibility with
previous versions to support operation in cells where the AU
uses SW version 3.X and lower.
Default selection is Disable.
 MIR: AU to SU (SU only) – Sets the Maximum Information Rate
of the down-link from the AU to the SU. The MIR value cannot
be lower than the corresponding CIR value.
Valid values are from 32 to 2200 Kbps.
The default value is 128 Kbps.
 MIR: SU to AU (SU only) – Sets the Maximum Information Rate
of the up-link from the SU to the AU. The MIR value cannot be
lower than the corresponding CIR value.
Valid values are from 32 to 2200Kbps.
The default value is 128Kbps.
 CIR: AU to SU (SU only) – Sets the Committed Information Rate
of the down-link from the AU to the SU. The CIR value cannot be
higher than the corresponding MIR value.
Valid values are from 0 to 2200Kbps.
The default value is 64Kbps.
 CIR: SU to AU (SU only) – Sets the Committed Information Rate
of the up-link from the SU to the AU. The CIR value cannot be
higher than the corresponding MIR value.
NOTE:
The value of the MIR/CIR option parameter must be the same for all Subscriber
Units served by the same AU (i.e. Enable for all SUs or Disable for al SUs).
Otherwise, throughput to/from all SUs in the cell may be reduced significantly.