Single sign on with multiple authentication factors

A method for authenticating a client computing device comprising a processing unit to multiple server resources each with a standalone authentication system, comprising;

• receiving a first set of login credentials from the client computing device to a first standalone authentication system of a primary one of the multiple server resources;
• validating the client computing device to the primary one of the multiple server resources based upon the first set of login credentials;
• transmitting to the client computing device a token generated by the first standalone authentication system in response to a successful validation of the first set of login credentials;
• receiving on a secondary one of the multiple server resources the token and a second set of credentials different from the first set of login credentials, wherein the second set of credentials comprises a second token and a personal identification code and is transmitted outside of the token and exists on the client computing device prior to the client computing device transmitting the first set of login credentials to the first standalone authentication system;
• and
• validating the client computing device by a second standalone authentication system of the secondary one of the multiple server resources based upon the received token and the second set of credentials.

A system comprising:

• a first authentication system;
• a second authentication system;
• and
• a client computing device comprising a processing unit and configured with instructions that, when executed, cause the client computing device to:
• initiate a login session with the first authentication system;
• transmit a first set of login credentials associated with a user of the client computing device to the first authentication system, wherein the first authentication system validates the client computing device based on the first set of login credentials;
• store a token generated by the first authentication system in response to the validation of the client computing device;
• and
• transmit the token and a second set of credentials to the second authentication system, wherein the second set of credentials comprises a second token and a personal identification code and is transmitted outside of the token and exists on the client computing device prior to the transmission by the client computing device of the first set of login credentials to the first authentication system, wherein the second authentication system validates the client computing device based on the token and the second set of credentials.