Patent ID: 8467512
Filing Date: 2013-06-18
Classification: H04M

Abstract:
1. A method of authenticating a source of a call from a caller to a recipient in a screening service, comprising: generating a caller account with the service including registration of a caller identity and registration of a digital signature associated with the caller; recording the registered caller identity and the digital signature with an authenticator; intercepting the call by a screener; receiving a proposed caller identity by the screener from the caller during the call including a phone number associated with the source of the caller; issuing a challenge by the screener to the caller; sending a return phone call from the screener to the caller using the phone number shown in the caller identity; verifying that the caller is in possession of the challenge; in response to verifying that the caller is in possession of the challenge, encrypting the issued challenge and the proposed caller identity by the caller using the digital signature; sending the encrypted challenge and the proposed caller identity from the caller to the authenticator; decrypting the encrypted challenge and the proposed caller identity at the authenticator and authenticating the source of the encrypted challenge by comparing the digital signature sent with the encrypted challenge against the digital signature registered in the caller account; forwarding the decrypted challenge and the proposed caller identity to the screener; verifying the decrypted challenge and the caller's registered caller identity match the issued challenge and the proposed caller identity received during the call; and passing the call to the recipient.