> Subscriber Overcharging Protection
> This chapter provides information on overcharging protection support for subscribers in UMTS network while loss of radio coverage occurred. The product Administration Guides provide examples and procedures for configuration of basic services on the system. It is recommended that you select the configuration example that best meets your service model, and configure the required elements for that model, as described in the respective product Administration Guide, before using the procedures in this chapter.
> Important: The features described in this chapter is an enhanced feature and need enhanced feature license. This support is only available if you have purchased and installed particular feature support license on your chassis.
> This chapter discusses following topics for feature support of Subscriber Overcharging Protection on loss of radio coverage for UE in UMTS networks:

> • | Introduction

> • | Supported Standards

> • | Supported Networks and Platforms

> • | Licenses

> • | Overcharging Protection Configuration

> • | Save the Configuration

> • | Verifying Your Configuration

> Introduction
> Mobile carriers typically are always looking for the solution for maximizing their network resource and, at the same time, looking for the method to effectively use of their network resource. Some mobile carriers charge their subscribers based on counts in x-CDR.
> Consider scenario where a mobile is using streaming services or downloading very large files from external sources and it goes out of coverage. If this download is happening on Background/Interactive traffic class then the GGSN is unaware of such loss of connectivity as SGSN do not the perform Update PDP Context procedure to set QoS to 0kbps (this is done when traffic class is either Streaming or Conversational only). The GGSN still keeps on sending the downlink packets to SGSN, the SGSN does paging and finds out the mobile is not responding. SGSN will then drop the packets. In such cases, the G-CDR will have increased counts but S-CDR will not have them.
> Some operators charge the subscribers based on G-CDR and overcharging can happen in the scenario given above. This feature is provided to avoid the overcharging is such cases.
> This feature uses private extension for Loss Of Radio Coverage (LORC) sent by SGSN in Update PDP Context message to set QoS to 0 kbps, on detecting loss of radio coverage of UE. GGSN becomes aware of the LORC status by recognizing the message (from SGSN) and discards the downlink packets if LORC status indicates loss of radio coverage and also stops discarding downlink packets, if LORC status indicates gain of radio coverage of UE.
> Supported Standards
> This is a proprietary feature and implemented on the basis of internal standards.
> Supported Networks and Platforms
> This feature supports Cisco® ASR 5000 Chassis with StarOS Release 9.0 or later running GGSN and/or SGSN service for the core network services.
> Licenses
> This feature support requires following feature license installed on the system:

> • | 600-00-7820

> Overcharging Protection Configuration
> This section provides a high-level series of steps and the associated configuration examples for configuring the system with overcharging protection to subscriber on loss of radio coverage for UE in GGSN services.
> Important: This section provides the minimum instruction set to configure the system to avoid the overcharging due to loss of radio coverage at the GGSN in UMTS network. Commands that configure additional function for this feature are provided in the Command Line Interface Reference.
> These instructions assume that you have already configured the system-level configuration as described in System Administration Guide and specific product Administration Guide.
> To configure the system to support overcharging protection on LORC in GGSN service:

> Step 1 | Configure the GTPC private extension in a GGSN service by applying the example configurations presented in the GTP-C Private Extension Configuration section below.

> Step 2 | Save the changes to system configuration by applying the example configuration found in Save the Configuration section of this chapter.

> Step 3 | Verify configuration of overcharging protection on LORC related parameters by applying the commands provided in the Verifying Your Configuration section of this chapter.

> GTP-C Private Extension Configuration
> This section provides the configuration example to configure the GTP-C private extensions for GGSN service:
> configure
> context <vpn_context_name>
> ggsn-service <ggsn_svc_name>
> gtpc private-extension loss-of-radio-coverage
> end
> Notes:

> • | <vpn_context_name> is the name of the system context where specific GGSN service is configured. For more information, refer GGSN Service Administration Guide.

> • | <ggsn_svc_name> is name of the GGSN service where you want to enable the overcharging protection for subscribers due to LORC.

> Save the Configuration
> To save changes made to the system configuration for this service, refer Verifying and Saving Your Configuration chapter.
> Verifying Your Configuration
> This section explains how to display and review the configurations after saving them in a .cfg file as described in Verifying and Saving Your Configuration chapter of this guide and also to retrieve errors and warnings within an active configuration for a service.
> Important: All commands listed here are under Exec mode. Not all commands are available on all platforms.
> These instructions are used to verify the overcharging protection support configuration.

> Step 1 | Verify that your overcharging support is configured properly by entering the following command in Exec Mode:

> show ggsn-service name ggsn_svc_name
> The output of this command displays the configuration for overcharging protection configured in the GGSN service ggsn_svc_name.
> Service name: ggsn_svc_name
> Context: service
> Accounting Context Name:service
> Bind: Done
> Local IP Address: 192.169.1.1 Local IP Port: 2123
> .
> .
> GTP Private Extensions:
> Preservation Mode
> LORC State

> Step 2 | Verify that GTP-C private extension is configured properly for GGSN subscribers by entering the following command in Exec Mode:

> show subscribers ggsn-only full
> The output of this command displays the LORC state information and number of out packets dropped due to LORC.

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