Telrad BreezeCOMPACT 1000 System Manual page 85

Chapter 3 - Operation and AdministrationBS Menu
Chapter 3: Operation and Administration
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.7.2.8 Scheduler
Scheduling uncommitted (above the maximum reserved rate) traffic can be done using one of the following options:

Equal Time (ET) scheduling mode, in which air resources are scheduled in a fair manner that is proportional to the users'
excess traffic (maximum sustained rate - maximum reserved rate) SLAs.

Equal Rate (ER) scheduling mode, in which air resources are allocated to users aiming at ensuring data rate fairness
between users proportional to their excess traffic SLAs.
Assuming a sector with diversity (different channels conditions) of active users, an ET scheme enables higher aggregate
sector throughput at the expense of data-rate fairness among users, while an ER scheduling scheme ensures maximum
data-rate fairness among users at the expense of lower aggregate sector throughput.
Using an ER scheduling scheme exposes the system to excessive allocation of air resources to highly active users having
relatively poorer channel conditions. To ensure data-rate fairness, more resources must be allocated to these users compared
to users with relatively good channel conditions. The effect of a small number of such users within the sector is reflected by
reduced aggregate sector throughput as well as degradation of achievable rates for all users.
To protect against abusing users, an instantaneous rate threshold can be defined within the scheduling scheme in which the
amount of air resources for users with continuous instantaneous rate below the threshold is being limited. The more the
abusing users' instantaneous rate is below the threshold, the more resource allocation limitations are applied.
Three levels of dynamic protection are available:

No protection.

Low protection level: Protection against users with very poor channel conditions. Should be used where the abusing
users' instantaneous rates are far below the average instantaneous rate within the sector.

Medium protection: Protection against users with relatively poor or very poor channel conditions. Should be used where
the abusing users' instantaneous rates are below or far below the average instantaneous rate within the sector.
A dynamic protection mechanism is implemented, in which the mechanism of limiting resource allocations is automatically
and dynamically activated when needed.
The Scheduler menu enables you to view/update the values configured for the following parameters:

Scheduler Mode

Scheduler DL Abuse Protection Level

Scheduler UL Abuse Protection Level
3.7.2.8.1 Scheduler Mode
The basis for allocating excess bandwidth among relevant users is as follows:

Equal Rate: Throughput Fairness

Equal Time: Resource Fairness
The selected mode applies for both uplink and downlink schedulers.
The default is Equal Rate.
BreezeCOMPACT System Manual BreezeCOMPACT System Manual
BS Menu
86