Validation and authentication

Range check

A number or date is within a sensible, allowed range

Type check

Data is of the right type, such as integer, letter or text

Length check

Text entered is not too long or too short- for example a password is between 8-15 characters

Presence check

Checks that data has been entered

Format check

Checks the format of, for example, a postcode or email address is correct

what is the purpose of validation

to make sure the inputs can’t be exploited

what is input validation

checking if data meets certain criteria before passing it into the program

what are authentication routines used for

Used to make sure a person is who they claim to be

what is a common method of authentication

Password routines- once user id has been entered the program looks up the password on a stored file.

What is verification used for

Used to double-check that the data has been types in correctly. e.g the user may be asked to type in the data correctly.