QoS Based Routing

In addition to configuring your system for routing based on certain session constraints, you can also set up routing based on QoS. QoS based routing uses the R-Factor on a per-realm basis to either cut back on the traffic allowed by a specific realm, or to shut that traffic off altogether.

To use this feature, you set up QoS constraints configurations and apply one per realm. The QoS constraints configuration allows you to set up two thresholds:

Major—The major threshold sets the R-Factor limit beyond which the Oracle® Enterprise Session Border Controller rejects a certain percentage (that you configure) of calls. That is to say, it rejects inbound calls at the rate you set with a 503 Service Unavailable status code, and rejects outbound calls if there are no alternative routes.
Critical—The critical threshold, when exceeded, causes the Oracle® Enterprise Session Border Controller to behave the same way it does when any of the session constraints (set in the session-constraints configuration) are exceeded. All inbound calls to the realm are rejected with a 503 Service Unavailable status code, and (if there is no alternate route) outbound calls are rejected, too. Until the R-Factor falls within acceptable means and the session constraint’s time-to-resume value has elapsed, the realm remains in this state.

Management

This feature is supported by MIBs and traps. Historical data recording (HDR) also supports this feature by providing the following metrics in the session realm statistics collection group:

Average QoS RFactor (0-93)
Maximum QoS RFactor (0-93)
Current QoS Major Exceeded
Total QoS Major Exceeded
Current QoS Critical Exceeded
Total QoS Critical Exceeded

QoS Contraints Configuration

This section shows you how to configure a QoS constraints configuration and then how to apply it to a realm.

Configuring QoS Constraints

Your first step to enabling QoS based routing is to set up a QoS constraints configuration. This configuration is where you enter major and critical thresholds, as well as the load reduction for the realm should the R-Factor exceed the major threshold.

To set up a QoS constraints configuration:

In Superuser mode, type configure terminal and press Enter.
```
ORACLE# configure terminal
ORACLE(configure)#
```

Type session-router and press Enter.

ORACLE(configure)# session-router
ORACLE(session-router)#

Type qos-constraints and press Enter.

ORACLE(session-router)# qos-constraints
ORACLE(qos-constraints)#

name—Enter the name of this QoS constraints configuration. This parameter uniquely identifies the configuration, and you use this value when applying the configuration to a realm. This parameter has no default and is required.
state—Set the state of this QoS constraints configuration. The default is enabled, but you can set this parameter to disabled if you want to stop applying these constraints.
major-rfactor—Enter a numeric value between 0 (default) and 9321 to set the threshold that determines when the Oracle® Enterprise Session Border Controller applies the call reduction rate. If you leave this parameter set to 0, then the Oracle® Enterprise Session Border Controller will not apply a major threshold for any realm where you apply this QoS constraints configuration.

Note that this value must be greater than that you set for the critical-rfactor, except when the major-rfactor is 0.
critical-rfactor—Enter a numeric value between 0 (default) and 9321 to set the threshold that determines when the Oracle® Enterprise Session Border Controller rejects all inbound calls for the realm, and rejects outbound calls when there is no alternate route. If you leave this parameter set to 0, then the Oracle® Enterprise Session Border Controller will not apply a critical threshold for any realm where you apply this QoS constraints configuration.

Note that this value must be less than that you set for the major-rfactor, except when the major-rfactor is 0.
call-load-reduction—Enter a number from 0 (default) to 100 representing the percentage by which the Oracle® Enterprise Session Border Controller will reduce calls to the realm if the major-rfactor is exceeded. If you leave this parameter set to 0, then the Oracle® Enterprise Session Border Controller will not reduce call load for the realm—even when the major-rfactor is configured.

This is the percentage of inbound and outbound calls the Oracle® Enterprise Session Border Controller will reject. For example, if you set this parameter to 50 and the major threshold is exceeded, then the Oracle® Enterprise Session Border Controller rejects every other call to the realm.
Save and activate your configuration.

Applying QoS Constraint to a Realm

You apply QoS constraints to realms using the qos-constraint parameter.

To apply a QoS constraint to a realm:

In Superuser mode, type configure terminal and press Enter.
```
ORACLE# configure terminal
ORACLE(configure)#
```

Type media-manager and press Enter

ORACLE(configure)# media-manager
ORACLE(media-manager)#

Type realm-config and press Enter. If you adding this feature to a pre-existing realm, then you need to select and edit that realm.
```
ORACLE(media-manager)# realm-config
ORACLE(realm-config)#
```
qos-constraints—Enter the name value from the QoS constraints configuration you want to apply to this realm.

Save and activate your configuration.