Quality of Service (QoS): Managing Bandwidth More Effectively
QoS Operating Notes and Restrictions
QoS Operating Notes and RestrictionsTablePacket Criteria or Restriction |
| QoS Types |
| DSCP Overwrite |
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| IP | Source Port | Incoming 802.1p |
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Restricted to IPv4 Packets Only | Yes | No | No | Yes |
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Allow Packets with IP Options1 | Yes | Yes | Yes | Yes |
Support IPv6 Packets2 | No | Yes | Yes | No |
Support | No | Yes | Yes | No |
1An “IP Option” is an optional, extra field in the header of an IP packet. If the switch is configured with a UDP/TCP type and a packet with an IP option is received, the switch uses the
2All Switches: For explicit QoS support of IPv6 packets, force IPv6 traffic into its own set of VLANs and then configure
■For Devices that Do Not Support 802.1Q
■Port Tagging Rules: For a port on the switch to be a member of a VLAN, the port must be configured as either Tagged or Untagged for that VLAN. For more on VLANs, refer to chapter 2, “Static Virtual LANs (VLANs)”.
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■RADIUS Authentication: RADIUS authentication allowing traffic through a given port may override the port’s QoS configuration, which generates an Event Log message. When the authenticated host discon- nects, the port returns to the static QoS configuration.
■Not Supported: Use of an inbound 802.1p packet priority as a type for remapping a packet’s outbound priority to different 802.1p priority. For example, where inbound packets carry an 802.1p priority of 1, QoS cannot be configured to use this priority as a type for changing the outbound priority to 0.