Chapter 4 - Operation and Administration

Table 4-15: CIR Ranges and Defaults

 

CIR Uplink

 

Unit

Range (Kbps)

Default (Kbps)

 

Type

 

 

 

SU-3

0-2,048

0

 

 

 

 

 

SU-6

0-4,096

0

 

 

 

 

 

SU-8

0-11,264

0

 

 

 

 

 

SU-54

0-45,056

0

 

 

 

 

 

SU-I

0-4,096

0

 

 

 

 

 

CIR Downlink

Range (Kbps)

 

 

Default (Kbps)

 

 

 

 

 

 

 

 

 

0-2,048

 

0

 

 

 

 

 

0-4,096

 

0

 

 

 

 

 

0-11,264

 

0

 

 

 

 

 

0-45,056

 

0

 

 

 

 

 

0-6,016

 

0

 

 

 

 

 

 

4.2.6.6.2.5 Maximum Burst Duration (SU and AU)

Sets the maximum time for accumulating burst transmission rights according to the Burst Duration algorithm.

Available values range from 0 to 2000 (milliseconds).

The default value is 5 (milliseconds), enabling a maximum burst of (0.005 X CIR) Kbps after a period of inactivity of 5 milliseconds or more.

4.2.6.6.2.6 Maximum Delay (SU only)

Sets the maximum permitted delay in the buffers system. As certain applications are very sensitive to delay, if relatively high delays are permitted, these applications may suffer from poor performance due to data accumulation in the buffers from other applications, such as FTP. The Maximum Delay parameter limits the number of available buffers. Data that is delayed more than the permitted maximum delay is discarded. If the SU supports applications that are very sensitive to delay, the value of the Maximum Delay should be decreased.

Valid values range from 300 to 10000 (milliseconds).

The default value is 5000 (milliseconds).

4.2.6.6.2.7 Graceful Degradation Limit (AU only)

Sets the limit on using the graceful degradation algorithm. In cases of over demand, the performance of all SUs is degraded proportionally to their CIR (IR=(100%-k%) x CIR). The graceful degradation algorithm is used as long as k ≤ K, where K is the Graceful Degradation Limit. Beyond this point the simple “brute force” algorithm is used. The Graceful Degradation Limit should be raised in proportion to the demand in the cell. The higher the expected demand in a cell, the higher the value of the Graceful Degradation Limit. Higher demand can be expected in cases of significant oversubscription and/or in deployments where a

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Alvarion SW VERSION 5.1 Maximum Burst Duration SU and AU, Maximum Delay SU only, Graceful Degradation Limit AU only