Cbwfq; Llq - HP ProCurve Secure Router 7203 dl Advanced Management And Configuration Manual

Setting Up Quality of Service
Overview
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Router
Queue
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Figure 7-1. First In, First Out
FIFO treats all packets in the same way. If you want the router to take packets'
ToS settings, or other criteria, into account when deciding how to treat them,
you must implement a different queuing method.
WFQ
WFQ is one method for granting differentiated service to packets with various
ToS values. When an interface uses WFQ, it classifies traffic flow into several
conversations, or subqueues, according to source and destination IP
addresses and protocol ports. The router then assigns each subqueue a weight
according to its IP precedence value and a bandwidth relative to its weight.

CBWFQ

CBWFQ is an extension of WFQ that allows network administrators to define
classes of conversation subqueues according to their own criteria. They can
also allocate bandwidth to these classes manually. Instead of the router
automatically assigning bandwidth to each subqueue based on relative IP
precedence, administrators assign each class of subqueue an absolute or a
relative amount of bandwidth.

LLQ

LLQ guarantees a set amount of bandwidth to certain types of traffic. It is a
better solution than WFQ for real-time traffic, such as VoIP, that cannot
tolerate jitter or delays.
LLQ also ensures that a router serves traffic in the low-latency queue first.
(See Figure 7-2.)
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