P-GW Administration Guide, StarOS Release 21.1

Feature Description

802.1p/MPLS EXP marking helps in providing QoS treatment by prioritizing traffic at L2 level.

Currently, data traffic for different access types, such as GGSN, eHRPD, P-GW, and S-GW, refer to the QCI-QoS table and configure the appropriate 802.1p or MPLS-EXP (L2 QoS) markings based on the internal-qos value associated with particular row. However, the usage of internal-qos from the QCI-QoS table is not configurable and uses the default values. In addition, L2 QoS (802.1p/MPLS EXP) marking is not supported in GGSN, SAEGW, and GTPv1/eHRPD calls on P-GW.

With this feature, you can:

Configure internal priority in QCI-mapping table for the GGSN, GTPv1 P-GW, and SAEGW calls.
Mark subscriber traffic with either 802.1p or MPLS-EXP to enable or disable L2 marking. A new CLI command has been introduced to support service specific configuration to mark subscriber traffic. This L2 marking can be decided based on QCI and DSCP marking together or solely based on DSCP marking.

Limitations

Limitations

This feature does not control the behavior of the control packets. The control packets (GTP-C) continue to get L2 marked based on DSCP derived L2 marking.
This feature is not supported on standalone GGSN. It is supported on GnGp-GGSN node.

How It Works

You can configure internal priority in QCI-mapping table for the GGSN, GTPv1 P-GW, and SAEGW calls. You can also mark subscriber traffic with either 802.1p or MPLS-EXP to enable or disable L2 marking. To do this, use the CLI command to configure service specific configuration to mark subscriber traffic. This L2 marking can be decided based on QCI and DSCP marking together or solely based on DSCP marking.

Behavior Changes for Different Services

Behavior Changes for Different Services

This section describes behavior of this feature for different services. Please see the Command Changes section for more information on the CLI command options and its behavior:

GGSN/P-GW GTPv1 Calls:

Previous Behavior: Earlier, the traffic was not marked for data path. This was default behavior for GGSN.

New Behavior: A new CLI command has been introduced to mark the traffic based on:

QCI-Derived
DSCP-Derived
None

If the no or default option of the CLI command is used, then the traffic is not marked. When the feature is not enabled, traffic is not marked.

P-GW GTPv2, S-GW, SAEGW Calls:

Previous Behavior: StarOS release 16 onward, the QCI-QoS mapping feature used internal-QoS for L2 marking, which in turn uses QCI-Derived marking for data traffic. This was the default behavior for P-GW, S-GW, and SAEGW calls.

New Behavior: With this feature, the traffic is marked based on:

QCI-Derived
DSCP-Derived
None

If the no or default option of the CLI command is used, then the traffic is not marked and the default behavior is executed. When the feature is not enabled, traffic is not marked.

Configuring Revised Marking for Subscriber Traffic

Earlier, the traffic was not marked for data path. This was default behavior for GGSN. Now, internal priority can be configured in QCI-mapping table for the GGSN, GTPv1 P-GW, and SAEGW calls. Subscriber traffic can also be marked with either 802.1p or MPLS-EXP to enable or disable L2 marking. To do this, use the CLI command to configure service specific configuration to mark subscriber traffic. This L2 marking can be decided based on QCI and DSCP marking together or solely based on DSCP marking.

Configuring Internal Priority
Verifying the Configuration

Configuring Internal Priority

To configure internal priority in the QCI-mapping table for the GGSN, GTPv1 P-GW, and SAEGW calls, use the following service specific configuration. This command in the GGSN service configuration overrides the behavior of QCI-QOS-mapping for data packets only.

configure
      context context_name
         ggsn-service service_name
            internal-qos data { dscp-derived | none | qci-derived }
            { no | default } internal-qos data { dscp-derived | none | qci-derived }
            end

Notes:

no: Disables the specified functionality.
default: Disables the functionality.
dscp-derived: Data packets are marked at Layer 2 based on DSCP configured in qci-qos mapping table, then if DSCP is not configured in the qci-qos mapping table then data packets are not marked.
none: Data packets are not marked with Layer 2 (MPLS EXP/802.1P) marking.
qci-derived: Data packets are marked at Layer 2 based on internal-qos-priority configured in qci-qos mapping table. If internal-qos priority is not configured in the qci-qos mapping table, then the data packets are not marked.

Verifying the Configuration

The configuration of this feature can be verified using the following commands from the exec mode:

show configuration
show service-type { all | name service_name }

Please see the Monitoring and Troubleshooting Revised Marking for Subscriber Traffic section for the command output.

Monitoring and Troubleshooting Revised Marking for Subscriber Traffic

The following section describes commands available to monitor Revised Marking for Subscriber Traffic.

Internal Priority Show Commands

Internal Priority Show Commands

The following section describes commands available to monitor Internal Priority.

show configuration
show service-type { all | name service_name }

show configuration

This command displays the following output:

When internal-qos data is configured as none:
```
internal-qos data none
```
When internal-qos data is configured as qci-derived:
```
internal-qos data qci-derived
```
When internal-qos data is configured as dscp-derived:
```
internal-qos data dscp-ds-derived
```
When internal-qos data is not configured:
```
no internal-qos data
```

show service-type { all | name service_name }

This command displays the following output:

When internal-qos data is configured as none:

Internal QOS Application:    Enabled
Internal QoS Policy:         None

When internal-qos data is configured as qci-derived:

Internal QOS Application:   Enabled
Internal QOS Policy:        QCI Derived

When internal-qos data is configured as dscp-derived:

 Internal QOS Application:    Enabled
 Internal QOS Policy:         DSCP Derived

When internal-qos data is not configured:

Internal QOS Application:     Backward-compatible

Book Title

Chapter Title

Results

Chapter: Revised Marking for Subscriber Traffic

Revised Marking for Subscriber Traffic