It is a practical way to add further security to the user logon sequence.
To understand Two Factor authentication, we need to know how a user can be authenticated. There are currently three ways:
- Something the user knows - PIN, Password, Secret.
- Something the user owns - Mobile Phone, Device.
- Something the user is - Bio-metric, retina, fingerprint.
Two factor authentication is a combination of any two of the above three ways. When this is applied to the business world it is usually made from " something the user knows and something the user owns". As using Bio-metrics is very expensive and very complicated.
There are simple examples of security breaches where systems were accessed simply through gaining access via simple username and password access. Two factor authentication makes life much more difficult for the determined hacker.