![](/images/backgrounds/285762/hp-procurve-2610-pwr-users-manual-550041234x1.png)
Quality of Service (QoS): Managing Bandwidth More Effectively
Using QoS Classifiers To Configure QoS for Outbound Traffic
b.Configure the switch to mark a specific type of inbound traffic with that DSCP (and thus create a policy for that traffic type).
c.Configure the internal switches in your LAN to honor the policy.
(For example, you could configure an edge switch to assign a codepoint of 000001 to all packets received from a specific VLAN, and then handle all traffic with that codepoint at high priority.)
For a codepoint listing and the commands for displaying and changing the
DSCP Policy table, refer to “Differentiated Services Codepoint (DSCP)
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| On switches covered in this guide, “mixing” ToS DSCP policies and 802.1p |
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| priorities is not recommended. Refer to the Note on page |
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| ■ Precedence Bits: This element is a subset of the DSCP and is comprised |
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| of the upper three bits of the ToS byte. When configured to do so, the |
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| switch uses the precedence bits to determine a priority for handling the |
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| associated packet. (The switch does not change the setting of the prece |
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| dence bits.) Using the ToS Precedence bits to prioritize IPv4 packets relies |
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| on priorities set in upstream devices and applications. |
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| Figure |
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| and illustrates the diffserv bits and precedence bits in the ToS byte. (Note that |
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| the Precedence bits are a subset of the Differentiated Services bits.) |
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| Field: | Destination | Source MAC | 802.1Q Field | Type & | ToS Byte | … |
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| MAC Address | Address |
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| Packet: | FF FF FF FF FF FF | 08 00 09 00 00 16 | 08 00 | 45 | E 0 | ... |
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Differentiated Services Codepoint
| Precedence |
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| Rsvd. |
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| Bits |
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1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 |
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| E |
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| 0 |
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