Abstract: A method for getting a device online, a method for sending addresses, a front-end device, a server and a surveillance system are provided, wherein the method for getting a device online includes: a front-end device carrying its own device identification to request a central management server for a registration; receiving a device address assigned by the central management server to the front-end device after the registration is successful; using the device address to request an online management server for getting online, receiving a request response fed back by the online management server. Through the above technical solution, the embodiment of the present invention solves the problem that the front-end devices need to be manually configured with device IDs one by one.