Abstract: Symmetric encryption device for protecting information between two end points, including in unicast mode, comprising: a central microprocessor (1), two RJ45 connectors (2) and (3), a protective locking module (4), which may be disabled for a predetermined time by means of software, for deleting information contained in the microprocessor or for destroying the latter, based on switches, diodes, or motion sensors, external communication ports (5), (Bluetooth, USB, RF) and a 9V battery (6) for supplying power to the locking system and to the microprocessor, used in an online unicast communication, a local network environment, a Multicast communication, or a bridge mode configuration. The encryption method may be used for acting as key server, adding/removing new users, certifying that the member sending the keys is the key seer and authentication between users.