What type of rule does 'Block if CVC verification fails' signify in Radar?

The type of rule 'Block if CVC verification fails' signifies a traditional card check. This kind of verification is a standard practice utilized during payment processing, focusing specifically on the Card Verification Code (CVC) as an added layer of security to verify that a customer is in possession of the physical card during a transaction.

When the CVC verification fails, it indicates that the information entered does not match what the issuing bank has on file, which raises suspicions about the legitimacy of the transaction. As a result, the traditional mechanism directly responds to this failure by blocking the transaction, helping to prevent potential fraud.

In contrast, machine learning card checks, 3DS checks, and automated fraud detection incorporate more sophisticated techniques that analyze various data points and patterns to assess the risk of a transaction. These methodologies go beyond a singular piece of information like the CVC and involve deeper data analytics to make real-time decisions on whether to allow or deny a transaction. Thus, they do not represent the primary mechanism indicated by the CVC verification rule, which is more straightforward and traditional in its approach.