"RSA SecurID ("SecurID") is a two-factor authentication
technology that is used to protect network resources. The
authentication is based on two factors -- something you know (a
password or PIN) and something you have (an authenticator). The
authenticator is typically a hardware token (such as a USB token,
smart card or key fob) and the software token is the RSA
Authentication Manager Software that provides the security engine
used to verify authentication requests.
"How RSA Secure ID Works: When a user attempts to access a
protected resource, he is prompted for a unique passcode. The
passcode is a combination of their user's PIN and the code that is
displayed on the authenticator token at the time of log in.
"The user ID and pass code are intercepted by the RSA
Authentication Agent and presented to the RSA Authentication
Manager software which validates the pass code. The RSA SecurID
system computes what number the token is supposed to be showing at
that moment in time, checks it against what the user entered, and
makes the decision to allow or deny access."