Validation and Verification


Entry Verification

Entry / Input Verification

Input verification is the process of checking that user has entered what the user intended to enter.

The most common input form of input verification is used in password creation. Whenever you enter a password on website when signing up for an account you are usually asked to enter your intended password twice in order to check that you have entered the same password twice. This is especially important when creating passwords because the inputted characters area normally replaced immediately with ****** so the user can’t be sure that they have entered the intended password correctly twice.


Data entry is verified by the use of a double password entry form


Transfer Verification

Data Transfer Verification

Data transfer verification is the process of ensuring that the data received is the same as the data sent. When data is transferred through a network at each stage there is possibility that data might get corrupted. Therefore when a packet is received it needs to be checked to ensure the integrity of the data. Two common ways this can be achieved is through the use of parity bits and check-sums.

Parity Bits tutorial




Input Validation

Input Validation

Validation is the process of checking that the user’s input matches the constraints of the system it is being entered into.

Common validation checks include:

  • Length checks
  • Format Checks
  • Range check
  • presence check
  • existence check
  • limit check
  • check digits(also functions as verification)
  • Password complexity checks
  • Password history checks
  • email address valid format check (make sure that it contains @ etc)



Here is a trinket example showing both entry verification and entry validation on a email/password signup form.


Class Slideshow

Parity Bit Google Sheets Demo  (You will have to File > Make a copy to edit it )

Exam Style Questions

  • Describe using examples, the difference between data verification and data validation.
  • Explain the verification and validation that occurs on a new user email sign-up form.

Programming Tasks

Programming tasks that work well with this topic.

  • Write a password verifier / validator
  • Write a Checksum checker (MOD 11)
  • Parity bit generator / checker