| Description | This object configures the QoS configured for Multicast
sessions replicated to any Downstream Channel
Set. It does not control which particular DCSs to which
the CMTS replicates a multicast session.
An instance in this object is called a GQC entry. A GQC
entry controls how the CMTS instantiates a Group Classifier
Rule (GCR) on the DCS to match packets of the multicast
session. A Group Classifier Rule (GCR) uses
source and destination IP address and ToS criteria.
A GQC entry controls how and with what QoS parameters
a Group Service Flow (GSF) is created on a DCS. All downstream
multicast packets are scheduled on a GSF. The
QoS Type attribute of the GQC entry controls whether
the CMTS creates one GSF for each single IP multicast
session or whether the CMTS creates one GSF for the aggregate
of all sessions that match the GQC criteria.
The GQC instance contains a reference to a Service Class
from docsIetfQosServiceClassTable. The Service
Class defines the list of QoS parameters for the GSF(s)
instantiated for the GQC entry.
A CMTS identifies one Service Class as the Default Group
QoS Service Class. The CMTS instantiates a Default
Group Service Flow on each single-channel DCS based
on the parameters of the Default Group QoS Service
Class.
The set of GCRs and GSFs instantiated on a DCS control
how QoS is provided to multicast packets replicated
to the DCS. For each multicast packet, the CMTS classifies
the packet to the highest priority matching GCR
on that DCS. The GCR refers to a single GSF, which controls
the scheduling of the packets on the DCS. If the
multicast packet does not match any GCR on the DCS, the
packet is scheduled on the Default Group Service Flow
of the DCS. The CMTS replicates unclassified multicast
traffic to only DCSs consisting of a single downstream
channel. Thus, the Maximum Sustained Traffic
Rate QoS parameter of the Default Group Service Class
limits the aggregate rate of unclassified multicast
traffic on each downstream channel.
The CMTS is expected to instantiate GCRs and GSFs controlled
by the entries in this table only for the duration
of replication of the multicast sessions matching
the entry.
This object supports the creation of multiple instances.
Creation of new instances of this object require the
following objects to be set:
ServiceClassName
QosCtrl
AggSessLimit |