Premium or high-risk numbers are phone numbers that connect callers to special services, often carrying higher charges compared to regular calls. These additional charges, paid to the service provider, place premium-rate numbers at a greater risk of exploitation through traffic pumping. Traffic pumping is a form of telecom fraud where bad actors artificially inflate traffic to their premium-rate numbers. When conducted internationally, this form of toll fraud is known as International Revenue Share Fraud (IRSF).
Plivo classifies numbers as premium or high-risk based on factors such as the associated rates, call patterns, susceptibility to toll fraud, and third-party trends.
Most businesses never need to contact premium rate numbers; therefore, by default, Plivo blocks calls to all phone numbers with high-risk prefixes to prevent unwanted charges.
Plivo has identified thousands of premium rate and high-risk prefixes. You can export a list of these prefixes in the Plivo console by navigating from Zentrunk > Geo Permissions > High-Risk Permissions. Plivo regularly updates this list based on factors such as the rates associated with the premium numbers, call patterns, and third-party trends.