HP 7102dl - ProCurve Secure Router Configuration Manual page 393

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The traffic placed in the queue receives priority above all other traffic until it
reaches the bandwidth specified in the command.
If the link is uncongested, priority traffic is allowed to burst up to the interface
rate; otherwise, priority traffic above the specified bandwidth can be dropped.
The router automatically calculates the burst value, which it uses to allow
traffic to temporarily burst above its maximum guaranteed limit. You should
almost always keep the default value. However, you can configure the burst
value manually with the priority command's <burst> option (range: 3 to
1,000,000). For example, enter:
ProCurve(config-qos-map)# priority 512 640
Allocating a Guaranteed Percentage of Bandwidth to a Low-Latency
Queue. Use the percent <value> option in the priority command to allo-
cate bandwidth as a percentage of the total interface bandwidth. This com-
mand is especially useful for protecting bandwidth allocation in multilink
applications. When one link fails in a multilink, the available bandwidth
changes. Allocating bandwidth by percentages ensures that each queue con-
tinues to receive only its proper share of the new total bandwidth.
If it is important that the high priority traffic receives a certain, set bandwidth
at all times, use the priority <bandwidth> command to specify this band-
width as an absolute amount.
To calculate the priority percent value, divide the minimum amount of band-
width needed for the traffic by the line rate (or the rate-limited data rate, if
this option has been configured on the interface). For example, to specify 80
Kbps of minimum bandwidth on an interface with a line rate of 512 Kbps (eight
E1 or T1 channels at 64 Kbps per channel), enter:
ProCurve(config-qos-map)# priority percent 16
Guaranteeing Unlimited Bandwidth to a Low-Latency Queue. If you
specify the unlimited option, priority traffic will take all of the bandwidth
available on the interface.
Do not assign a queue unlimited bandwidth lightly. Even if the traffic in the
queue is important, it is rarely critical enough to be worth starving out all other
traffic. For example, it could even starve out a Telnet or HTTP session with
the router.
Setting Up Quality of Service
Configuring LLQ
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