Cisco cBR 8 Configuration Guide

Information About DOCSIS WFQ Scheduler
The DOCSIS WFQ scheduling engine is used to provide output packet scheduling services, including absolute
priority queueing, weighted fair queueing, minimum rate guarantee, traffic shaping, and DOCSIS bonding
group dynamic bandwidth sharing on the Cisco cBR-8 converged broadband router.
The DOCSIS WFQ Scheduler provides services on both WAN uplink interfaces and DOCSIS downstream
interfaces. The scheduling parameters on WAN uplink interfaces are configured through the Modular QoS
CLI (MQC). On cable downstream interfaces, queues are created for DOCSIS service flows with parameters
configured by DOCSIS downstream QoS type, length, values (TLVs).
The default queue size for the DOCSIS service flows (with bandwidth greater than 150 Mbps) is based on
the bandwidth on the cable downstream interfaces (see Table below). Additionally, the queue limit for all
service flows can also be adjusted using the cable queue-limit command, buffer size in service class or
downstream buffer control TLVs.
The default queue size change, and the cable queue-limit command do not affect the DOCSIS high priority
queues.
Note
Table below is an example of the queue size based on Annex B 256 QAM channels.
Table 18: Bandwidth, Queue Sizes, and Queue Limits
Queue SizeDefault
Queue Size
Bandwidth
(Mbps)
Channel
200 ms40 ms30 ms20 ms1 ms
6171239263636337.51
123524718512363255752
185237027718563255112.53
2470494370247632551504
308761746330863319187.55
3705741555370633832256
432386464843263447262.57
4940988741494635113008
7411148211117416376745012
8646172912968646389552514
98811976148298863102360016
Cisco cBR Series Converged Broadband Routers Quality of Services Configuration Guide for Cisco IOS XE Fuji
16.7.x
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DOCSIS WFQ Scheduler on the Cisco CMTS Routers
Information About DOCSIS WFQ Scheduler

Cisco cBR 8 Specifications

General

Brand	Cisco
Model	cBR 8
Category	Network Router
Language	English