Class CIM_REDDropperService
extends CIM_DropperService

REDDropperService represents the ability to drop network traffic using a Random Early Detection (RED) algorithm. The purpose of a RED algorithm is to avoid congestion (as opposed to managing congestion). Instead of waiting for the queues to fill up, and then dropping large numbers of packets, RED works by monitoring average queue depth. When the queue depth exceeds a minimum threshold, packets are randomly discarded. These discards cause TCP to slow its transmission rate for those connections that experienced the packet discards. Other connections are not affected by these discards. A RED dropper always drops packets from a single queue, which is related to the dropper as the following Service in the NextService association. The queue(s) examined by the drop algorithm are found by following the CalculationServiceForDropper association(s) to determine the dropper's DropThresholdCalculationService(s), and then following the CalculationBasedOnQueue association to find the queue being watched by each CalculationService.

Table of Contents
Hierarchy
Direct Known Subclasses
Class Qualifiers
Class Properties
Class Methods

Class Hierarchy

CIM_ManagedElement
   |
   +--CIM_ManagedSystemElement
   |
   +--CIM_LogicalElement
   |
   +--CIM_EnabledLogicalElement
   |
   +--CIM_Service
   |
   +--CIM_ConditioningService
   |
   +--CIM_DropperService
   |
   +--CIM_REDDropperService

Direct Known Subclasses

Class Qualifiers

NameData TypeValue
DescriptionstringREDDropperService represents the ability to drop network traffic using a Random Early Detection (RED) algorithm. The purpose of a RED algorithm is to avoid congestion (as opposed to managing congestion). Instead of waiting for the queues to fill up, and then dropping large numbers of packets, RED works by monitoring average queue depth. When the queue depth exceeds a minimum threshold, packets are randomly discarded. These discards cause TCP to slow its transmission rate for those connections that experienced the packet discards. Other connections are not affected by these discards. A RED dropper always drops packets from a single queue, which is related to the dropper as the following Service in the NextService association. The queue(s) examined by the drop algorithm are found by following the CalculationServiceForDropper association(s) to determine the dropper's DropThresholdCalculationService(s), and then following the CalculationBasedOnQueue association to find the queue being watched by each CalculationService.
UMLPackagePathstringCIM::Network::QoS
Versionstring2.7.0

Class Properties

Local Class Properties

NameData TypeDefault ValueQualifiers
NameData TypeValue
MaxQueueThresholduint32
DescriptionstringThis is an unsigned 32-bit integer that defines the maximum average queue length at which packets are subject to always being dropped, regardless of the dropping algorithm and probabilities being used. (See the ThresholdUnits property to determine the units of the threshold.)
MaxValuesint641000
MinValuesint640
ModelCorrespondencestringCIM_REDDropperService.ThresholdUnits
MinQueueThresholduint32
DescriptionstringThis is an unsigned 32-bit integer that defines the minimum average queue depth at which packets are subject to being dropped. (See the ThresholdUnits property to determine the units of the threshold.) The slope of the drop probability function is described by the Start/StopProbability properties.
ModelCorrespondencestringCIM_REDDropperService.ThresholdUnits
StartProbabilityuint32
DescriptionstringThis is an unsigned 32-bit integer, used in conjunction with the StopDropProbability property. The start and stop probabilities define the slope of the drop probability function. This function governs the rate at which packets are subject to being dropped, as a function of the queue length. This property expresses a drop probability in drops per thousand packets. For example, the value 100 indicates a drop probability of 100 per 1000 packets, that is, 10%. Min and max values are 0 to 1000.
ModelCorrespondencestringCIM_REDDropperService.StopProbability
PUnitstringcount / packet * 10^-3
UnitsstringPer Thousand Packets
StopProbabilityuint32
DescriptionstringThis is an unsigned 32-bit integer, used in conjunction with the StartDropProbability property. The start and stop probabilities define the slope of the drop probability function. This function governs the rate at which packets are subject to being dropped, as a function of the queue length. This property expresses a drop probability in drops per thousand packets. For example, the value 100 indicates a drop probability of 100 per 1000 packets, that is, 10%. Min and max values are 0 to 1000.
MaxValuesint641000
MinValuesint640
ModelCorrespondencestringCIM_REDDropperService.StartProbability
PUnitstringcount / packet * 10^-3
UnitsstringPer Thousand Packets
ThresholdUnitsuint16
DescriptionstringThresholdUnits is an enumerated integer that identifies the units for the Min and MaxQueueThreshold properties. The values are either bytes (1) or packets (2).
ValueMapstring1, 2
ValuesstringBytes, Packets

Inherited Properties

NameData Type
AlwaysDropuint16
Captionstring
CommunicationStatusuint16
CreationClassNamestring
Descriptionstring
DetailedStatusuint16
DropFromuint16
DropMaintainMetricuint16
DropperTypeuint16
DropStartMetricuint16
ElementNamestring
Enabledboolean
EnabledDefaultuint16
EnabledStateuint16
Generationuint64
HealthStateuint16
InstallDatedatetime
InstanceIDstring
LoSIDstring
LoSOrgIDstring
Namestring
OperatingStatusuint16
OtherDropperTypestring
OtherEnabledStatestring
PrimaryOwnerContactstring
PrimaryOwnerNamestring
PrimaryStatusuint16
RequestedStateuint16
Startedboolean
StartModestring
Statusstring
SystemCreationClassNamestring
SystemNamestring
TimeOfLastStateChangedatetime
TransitioningToStateuint16
AvailableRequestedStatesuint16[]
OperationalStatusuint16[]
StatusDescriptionsstring[]

Class Methods

Inherited Class Methods

NameReturn Type
ChangeAffectedElementsAssignedSequenceuint32
RequestStateChangeuint32
StartServiceuint32
StopServiceuint32