Communications methods and appliances are described. According to one embodiment, a communications method includes prior to deployment of an appliance, establishing a trusted association between the appliance and a certificate authority, during deployment of the appliance, associating the appliance with a communications address of a communications medium, using the certificate authority, creating a signed certificate including the communications address of the appliance, announcing the signed certificate using the appliance, after the announcing, extracting the communications address of the appliance from the signed certificate, and after the extracting, verifying the communications address of the appliance.