News & Events

Fighting Voice Fraud with Call Line Identification

Consumers experience Voice fraud through spam calls that either have no one on the line or playback a recorded voice. What might only be a nuisance to us is actually costing the telecoms industry $17 billion a year, according to the Communication Fraud Control Association (CFCA).

There’s growing instances of nuisance callers changing their caller ID, especially with Voice over IP (VoIP). Nearly half of all calls to mobile phones next year will be made by scammers, according to new research from First Orion, a US-based developer of Caller ID technology. Call Line Identification (CLI) enables a person receiving a call to see the caller’s number, just like Caller ID. CLI data can be used to trace and identify the source of a nuisance call or as a way to identify the location of a caller in an emergency situation. For this to be effective, the data needs to be provided correctly and delivered across networks accurately.

For the management of IP Multimedia Subsystem (IMS) based services, CLI is a key requirement for roaming, charging and operational practices. Over the last few years it’s become really important due to the introduction of Origin Based Calling. It determines the price from its origin, in addition to where the call is going. When the origin is reliable there’s less fraud and more accurate billing.

The CLI transmits a caller’s telephone number to the other caller’s telephone equipment when it’s being set up. Whether the service is successfully shown to the callee all depends on the operators’ service capabilities.

If the service is supported in an international IMS environment, it’s required that international IPX Providers pass on the CLI unaltered. Under normal operational conditions IPX Providers are not expected to check CLI validity.

They can’t guarantee that:

  • The CLI will be transmitted by the originating Service Provider
  • The CLI received from the originating Service Provider is a valid value, i.e. a value of a CLI owned or ported to Service Provider, and indeed, is the correct CLI for the calling party
  • The CLI forwarded to an interconnecting IPX Provider will be delivered to the terminating user, or delivered without any error being introduced beyond the interconnecting IPX Provider


By following our CLI Management guidelines, you can ensure origin and billing parameters are reliable with less risk of fraud.

At i3forum, we provide a platform for open discussion by working with thought leaders to deliver valuable content for the wider industry. Our Technology group work together to establish best practice and guidelines for the whole industry. The group analyses the use of IMS in existing and new services as well as interoperability issues related to IMS-based platforms with a focus on Voice and covers both basic international call and roaming, and advanced communication services.

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