Motorola BSR 2000, Руководство по настройке и управлению

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BSR 2000 Configuration and Management Guide Release 1.0
6-98 MGBI 526360-001-00 Rev. B
Scheduling Priority
The scheduling priority of a service class determines the order in which service flows
are serviced by the packet scheduling algorithm. All service flows belonging to a
service class with a higher scheduling priority will be serviced before service flows
belonging to service classes with a lower scheduling priority. Class scheduling
priority is distinct from the DOCSIS QoS parameter, traffic priority, which is
specified to differentiate priority for service flows with other-wise identical QoS
parameter sets.
Admission Control
Admission control is a process wherein the bandwidth requirements of a service flow
are checked to verify that admission of the service flow to a service class does not
exceed the class’ MAB after accounting for the allowed level of overbooking. Service
flows are created during modem registration or through dynamic service messaging.
A CM registering with primary service flows will be permitted to register regardless
of whether the admission of its service flows would exceed its service class’ MAB. In
this case the service flow will be admitted in a ‘Restricted’ state meaning that the
service flow will not be provided any guaranteed minimum reserved rate. Service
flows created via dynamic service messaging will be rejected if admission of the
service flow would cause its service class to exceed its MAB.
Default Service Classes
All service flows must be assigned to a service class. If a service class name is not
present in a Registration Request message generated by a CM, then the CM service
flows are assigned to a default service class based on the direction, scheduling service
type, and the specified minimum reserved rate for the service flows.
Table 6-13 describes the eight default service classes on the BSR:
Note: The parameters of the default service classes may be modified but the
default service classes cannot be deleted. Refer to Modifying Service Class
Parameters for more information on changing service class parameters.