Patent ID: 7613919

Claim:
At an authentication service in a computerized environment that includes a client, a service provider, and an authentication service, a method of the authentication service authenticating the client to the service provider using a one-time password that was previously exchanged between the authentication service and the client, the method comprising the acts of: the authentication service generating an authentication service identifier for the client; the authentication service receiving a client moniker from the client; after receiving the client moniker, the authentication service sending a one-time password to the client for the client to use in accessing the service provider; after sending the one-time password to the client, the authentication service receiving a one-time password from the service provider; if the one-time password received from the service provider matches the one-time password sent by the authentication service to the client, then the authentication service sending the authentication service identifier for the client to the service provider to authenticate the client; and if the one-time password received from the service provider does not match the one-time password sent by the authentication service to the client, then the authentication service indicating to the service provider that the one-time password received from the service provider does not match the one-time password sent to the client.