International Telecommunication Charge Card

Description

The International Telecommunication Charge Card (ITCC) is a service defined in 3GPP TS 29.163 that allows a subscriber to charge telecommunication services (such as voice calls, SMS, or data sessions) to a specific charge card account, rather than to their primary mobile subscription. This is particularly useful in scenarios like international roaming, where a user might want to avoid high roaming charges by using a separate, pre-paid international calling card. The ITCC service involves interactions between the visited network (where the user is roaming), the home network, and potentially a third-party Charge Card Service Provider (CCSP).

Technically, the service is enabled through enhancements to the Camel (Customised Applications for Mobile network Enhanced Logic) Application Part (CAP) protocol. When a user initiates a call and indicates the use of an ITCC (e.g., by dialing a special prefix or number), the Visited Mobile Switching Centre (VMSC) or Serving GPRS Support Node (SGSN) triggers a Camel dialogue with a dedicated Service Control Point (SCP) known as the Charge Card SCP. This SCP is responsible for authenticating the charge card (using credentials like a card number and PIN), checking the account balance for pre-paid cards, and authorizing the service. The SCP then instructs the visited network's switch to connect the call, often via a specific route, and manages real-time charging events.

The protocol defined in TS 29.163 specifies the information flows and CAP operations for ITCC service invocation, including initial DP (Initial Detection Point) triggers, request and response messages for card validation, and charging events. The architecture separates the call control function in the visited network from the service logic and charging function in the Charge Card SCP. This allows for centralized management of card accounts and enables service portability across different visited networks. The service can support various charging models, including debit from a pre-paid balance or accumulation on a post-paid invoice.

Purpose & Motivation

The International Telecommunication Charge Card service was created to address the need for flexible, alternative payment methods for telecommunications, especially in cross-border scenarios. Before its standardization, proprietary calling card systems existed, but they lacked interoperability between different network operators and countries. A traveler would need a different card or mechanism for each visited country. The ITCC standard aimed to provide a unified, operator-agnostic method for using charge cards, simplifying the user experience and enabling global service offerings from charge card providers.

It solves the problem of high and unpredictable roaming charges by allowing users to segregate costs. A user can maintain a primary subscription for local use and a separate, potentially pre-paid, charge card account for international calls or data. This gives users more control over spending. For operators and third-party service providers, it creates a new business model and revenue stream through the provision of charge card services, including international calling cards sold at retail or online.

The motivation was also technical: to define a clean, standardized interface between the network performing call control and the external entity managing the charge card logic and balance. Using the existing Camel infrastructure for intelligent network services provided a proven, scalable framework. This avoided the need for operators to develop bespoke, non-interoperable solutions for integrating third-party charging systems, thereby reducing costs and complexity while fostering a competitive market for value-added services.

Key Features

• Enables charging services to a separate card account, distinct from the primary subscription
• Utilizes Camel (CAP) protocols for service control and triggering
• Supports both pre-paid and post-paid charging models
• Facilitates use in international roaming scenarios
• Involves a dedicated Charge Card Service Control Point (SCP) for authentication and authorization
• Defines standardized information flows between visited network and charge card server (TS 29.163)

Evolution Across Releases

Defining Specifications