Skip to main content

Keep the last n digits and replace previous ones

This function keeps the last n digits as is and replaces previous ones with digits. Non-digits characters remain as is.
Option Description
Method The Randomly method randomly selects a character. As a result, two identical input values can be masked with the different output values.

When the same value appears twice in the input data, the Consistently method ensures that the function outputs the same masked value in the same Job execution.

This function can encrypt the output masked values in the same format as the input values, using Format-Preserving Encryption (FPE) methods:

  • FF1 with AES relies on the Advanced Encryption Standard in CBC mode.
  • FF1 with SHA-2 relies on the secure hash function HMAC-256.

The FPE methods are bijective methods, except when using tweaks.

The FF1 with AES and FF1 with SHA-2 methods require a password to generate encrypted and repeatable masked values. Those FPE methods do not use a seed.

You can specify this password in the Password or 256-bit key for FF1 methods field, from the Advanced Settings of the component.

Extra parameter This function requires an extra parameter.

The extra parameter is the number of digits to be masked.

In the first example, the input value does not contain any digits, the input value is copied as is to the output.

In the second example, the last two digits are copied to the output as is. The previous ones are masked with random digits.

Input value Extra parameter Example of a masked value
Jack "2" Jack
S1000D "2" S8900D

Did this page help you?

If you find any issues with this page or its content – a typo, a missing step, or a technical error – let us know how we can improve!