# Create QoS Class elements

QoS Classes are used to collect QoS statistics about traffic or to create a link between the Access rules and the QoS Policy.

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When traffic matches an Access rule, the QoS Class defined in the rule is applied to the traffic. You can also use QoS Classes in Outbound Multi-Link elements to adjust the load balancing of different types of connections.

There is a default QoS Policy and three default QoS Classes. The classes can be used to set priorities for high, normal, and low priority traffic, without any bandwidth guarantees or limits.

You must create one QoS Class for each rule you plan to add in any single QoS Policy, as the QoS Policy cannot contain any overlapping rules. You can create as many QoS Classes as necessary. The QoS Policy must not have overlapping rules. You must create one QoS Class for each rule you plan to add to the QoS Policy (each type of traffic must have its own QoS Class). The same QoS Class can be used in multiple Access rules, so several Access rules can point matching traffic to the same QoS rule.

For more details about the product and how to configure features, click Help or press F1.

## Steps

1. Select Configuration, then browse to SD-WAN.
2. Browse to Other Elements > QoS Classes.
3. Right-click QoS Classes, then select New QoS Class.
4. Configure the settings, then click OK.

## Result

The new QoS Class is added to the resources and can now be used in policies.

## QoS Class Properties dialog box

Use this dialog box to define the properties of a QoS Class.

Option | Definition
--- | ---
Name | The name of the element.
Override Link Selection Preferences set in Network Applications and Protocol Agents | When selected, the link selection options defined in the QoS Class element override the default link selection options in the properties of Network Application elements and Protocol elements of the Protocol Agent type. Selecting this option allows you to edit the other link selection options.
Bandwidth | Specifies how important the bandwidth of the connection is for determining which link traffic uses.
Jitter | Specifies how important variations in the delay of received packets is for determining which link traffic uses.
Latency | Specifies how important delays in packet transmission are for determining which link traffic uses.
Packet Loss | Specifies how important the number of packets of data that fail to reach their destination are for determining which link traffic uses.
Stability | Specifies how important variations in the availability and quality of the connection are for determining which link traffic uses.
Category (Optional) | Includes the element in predefined categories. Click Select to select a category.
Comment (Optional) | A comment for your own reference.