Last Updated: 07/31/2020

UE Usage Metering

Magma currently supports basic usage metering. This allows for real-time monitoring of data usage specified with the following labels:

• IMSI
• session_id
• traffic direction

This feature is currently built to enable post-pay charging.

Metering information is available through our metrics REST endpoint. The metric name used is ue_traffic.

Configuring Metering

As a pre-requisite, ensure you have the following:

• a functional orc8r
• a configured LTE network
• a configured LTE gateway with eNodeB
• subscribers that can attach to your LTE gateway
• network running in un-federated mode

In un-federated mode, the policydb service on the LTE gateway acts as a lightweight PCRF, and federated support for metering is not currently supported.

To enable metering for a single subscriber, the following steps need to be completed:

1. A rating group configured with infinite, metered credit
2. A policy rule configured with the above rating group
3. Your policy rule assigned to the subscriber to be metered

If you do not have a NMS setup with integration to Magma's REST API, the details below should help. If your orc8r is functional, you should be able to manually access the Swagger API.

Configuring Rating Group

/networks/{network_id}/rating_groups

Configure with the following JSON as an example. Modify the ID as necessary.

{
  "id": 1,
  "limit_type": "INFINITE_METERED"
}

Configuring Policy Rule

/networks/{network_id}/policies/rules

Configure with the following JSON as an example. Here, the flow list is set to allow all traffic. A high priority is also set to override other rules. You may need to modify the rating_group to match the ID of the rating group you configured earlier. Here you also have a chance to directly assign the policy to the subscriber you wish to meter for.

{
  "app_name": "NO_APP_NAME",
  "app_service_type": "NO_SERVICE_TYPE",
  "assigned_subscribers": [],
  "flow_list": [
    {
      "action": "PERMIT",
      "match": {
        "direction": "UPLINK",
        "ip_proto": "IPPROTO_IP"
      }
    },
    {
      "action": "PERMIT",
      "match": {
        "direction": "DOWNLINK",
        "ip_proto": "IPPROTO_IP"
      }
    }
  ],
  "id": "metering_rule",
  "priority": 10,
  "qos": {
    "max_req_bw_dl": 0,
    "max_req_bw_ul": 0
  },
  "rating_group": 1,
  "tracking_type": "ONLY_OCS"
}

Assigning Policy to Subscriber

/lte/{network_id}/subscribers /networks/{network_id}/policies/rules/{rule_id}

Two endpoints can be used for assigning the metering policy to a subscriber. Set the assigned_subscribers field for a policy rule, or set the active_policies field for a subscriber.

Verifying Metering

It may take up to a minute for the update configurations to propagate to the LTE gateway, where they should be received and stored by policydb.

Check the metrics REST endpoint to verify that metering data is being recorded.

Debugging Metering

On subscriber attach, policydb will provide the metered policy to install for the subscriber. By tailing these logs, it is possible to verify that the configurations are being received. journalctl -fu magma@policydb

pipelined is the service which is responsible for enforcement, by use of OVS. By using the CLI tool, it is possible to verify that the policy rule is being installed for the user. The policy id will be listed if installed, along with tracked usage. pipelined_cli.py debug display_flows This command may need to be run as root.

sessiond is responsible for aggregating metrics and sending metering through our metrics pipeline. To check the tracked metrics for metering, and the sessiond service, run the following: service303_cli.py metrics sessiond