Advanced Configuration and Management Guide
Figure 4.6 shows an example of two Committed Time Intervals. In this example, the policy rule matches the maximum number of conforming bytes (Normal Burst Size bytes) in each interval.
1000Mbps port
Excess Burst packets - received after maximum number of Normal Burst packets are received within the Committed Time Interval. The Exceed action applies to these packets.
Excess Burst Counter restarts at zero at the beginning of every second Committed Time Interval.
Normal Burst packets - The Conform action applies to these packets.
Normal Burst Counter restarts at zero at
the beginning of each Committed Time Interval.
Once maximum Excess Burst Size is reached, traffic is dropped.
Line rate = 1,000,000,000 bps (one Gigabit)
Average Rate = 500,000,000 bits
Normal Burst Size = 62,500,000 bytes (500,000,000 bits)
Excess Burst Size = 93,750,000 bytes (750,000,000 bits)
Committed Time Interval = 1 second
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Packets received here are dropped.
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| Zero - 500,000,000 |
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| Zero - 500,000,000 |
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| 500,000,000 received in |
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| 500,000 received in |
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| Interval |
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| 500,000,001 - 750,000,000 |
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| 175,000,000 bits received in | ||
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| 75,000,000 bits received in | ||
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| interval are dropped. | ||
Figure 4.6 Excess Burst Size increments over every two Committed Time Intervals
The rule matches additional bytes in each interval, and thus applies the exceed action. The counter for the Excess Burst Size increments over the span of the two intervals. Thus, the number of Excess Burst Size bytes available for the second interval is the amount that remains after the first Committed Time Interval. In this example, the rule matches 175,000,000 bits of additional (Excess Burst Size) data in the first Committed Time Interval. The Excess Burst Size in the rule is set to 250,000,000 bits. As a result, only 75,000,000 Excess Burst Size bits are available for use by the traffic that matches the rule in the second Committed Time Interval.
After the rule matches the maximum number of Normal Burst Size bytes in the second Committed Time Interval, the rule matches an additional 75,000,000 bits. The software drops all bytes received in the second Committed Time Interval after the Excess Burst Size maximum is reached.
Regardless of the actions for conforming and exceed traffic, the interface drops all traffic that matches a rule after the rule has matched the maximum number bytes for the rule’s Normal Burst Size and Excess Burst Size.
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