Authentication Factors

There are three categories of authentication factors:

1. Ownership Factor
2. Knowledge Factor
3. Inherence Factor

Any good authentication system should be using at least two of these.

An Ownership Factor looks at what you have. This could be your ATM card, one of those RSA Tokens with the number that is always changing, or even a simple key on your key ring.

The Knowledge Factor is an examination of something you know such as the PIN number for that ATM card, a password or the answer to a challenge question.

Finally, the Inherence Factor looks for something you are. This could by your fingerprint or some other physical trait that is only yours. You'll hear this called biometrics.