Why is authentication necessary?
Authentication is the verification of the identity of a person or entity: it is proving that you are the one you pretend to be.
Authentication is continuously present in our lives:
you access your e-mail with a password
you enter a PIN to unlock your mobile
you show your passport in the airport
you place orders with your signature
Authentication is necessary because some level of dishonesty is a component of human nature present at least to some extent in most people.
What is an authentication factor?
An authentication factor is a piece of information and process used to authenticate or verify a person’s identity for security purposes.
Examples are password, PIN, photograph on ID card, pen signature, smart card.
There are three types of authentication factors:
“Something you know”, such as password or PIN code.
“Something you have”, such as a certificate or a key in a security hardware device (like a Smartcard)
“Something you are”, these are biometric factors like fingerprints, vein scans, iris scans or facial or speech recognition
What is strong authentication?
Strong authentication is an authentication that combines at least two authentication factors of different types to enhance the security of the verification of the identity.
Using two factors of different types as opposed to one delivers a higher level of authentication assurance.
The most common example is using the credit card (something you have) with a PIN code (something you know).
Accessing an email account with username and password is not strong authentication: the username is your identity and the password is the sole authentication factor (something you know).
Why are multiple factors more secure?
It is easy to steal a Smartcard, but more difficult to steal also the PIN code that is necessary to use it.
It is the combination of the factors that enhances the security.