QoS on Input

Priority levels range from 0 (lowest) to 7.

6.Create a traffic policy. policy-map<policy-map-name>

7.Optional. Mark the IEEE 802.1 priority in the output VLAN header. set cos <0 - 7>

8.Attach the service policy to the input or output interface.

interface <Interface name> <slot/card/number> service-policy <input output> <policy-map-name>

You can set the service policy on an incoming or outgoing interface.

Refer to “QoS with VLAN Policy” on page 12-28for a configuration example.

QoS on Input

QoS on input and QoS on output share a common configuration and set of features. QoS on input is configured with a policy map in the same way as Qos on output - with the service-policy input policy-map-namecommand. One policy map may be applied at the same time on one interface as input and on the other as output. QoS features that are configured on the policy map but are not applicable to input direction are automatically removed by the XSR.

QoS on input shares the following features with the Qos on output:

Classification by class-maps: Both QoS on input and output provide classification

Marking per traffic flow: QoS on input marks DSCP and IP precedence fields

Policing per traffic class with actions for exceed and violate traffic

An exception to the shared qualities: QoS on input does not buffer packets - it applies QoS actions on a packet-per-packet basis with no buffering. Other output QoS features not performed by QoS on input include:

Shaping

Bandwidth sharing with the bandwidth command

Prioritization with the priority command

Marking of the CoS bit in the VLAN header

RED or WRED

For QoS on Input configuration examples, refer to “Input and Output QoS Policy” on page 12-28and subsequent examples.

QoS on VPN

QoS on VPN provides classification, policing, marking, shaping, and prioritization for managing traffic that transits VPN tunnels. The XSR’s implementation of QoS on VPN uses a class-based interface for configuring QoS similar to QoS configuration on other non-VPN interfaces.

In a typical VPN environment, packets are encrypted and/or encapsulated in VPN tunnels. The original packet header (inner header) and its contents are modified and encapsulated in a new packet with a new header (outer header). At the output physical interface only the outer header is visible. This situation presents a challenge for QoS on the output interface to identify and classify packets based on the inner header and their original content. But it is addressed by the XSR’s support of copying ToS bits from the inner to the outer header with the copy-toscommand.

XSR User’s Guide 12-17

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Enterasys Networks X-PeditionTM manual QoS on Input, QoS on VPN