A system and method of authenticating the identity of a remote fax machine during a faxing operation is provided. An X.509-type Certificate received from the remote fax machine is validated to affirm it can be properly associated with the remote machine. The Certificate's public key is used to verify the remote fax machine has the corresponding private key. A Certificate's Common Name then compared to an Expected Name to authenticate the identity of the remote fax machine prior to sending a fax to prevent an unwanted misdirection of faxed information and to screen incoming faxes for unwanted spam.