|  |  | The Cisco Secure IDS consists of 3 major components: the sensor, director, and post office. The sensor is a network device that is installed at both the entry and exit points of the network you wish to protect. It gathers information from the network and forwards it to the director, which is the central management location for the sensors. At the director, the user can utilize a GUI to review data on the sensors and issue orders to the sensors. Communication between the sensors and the director is accomplished via the post office. The post office is a proprietary communications protocol.