A system, comprising: - a controller device (109, 209) comprising user interface equipment configurable with software, wherein the controller device is arranged to transmit a control message comprising an identifier of the controller device that identifies the controller device from other controller devices, - at least one electrical device (101, 102, 201, 202, 203, 204) comprising functional elements for carrying out actions defined by the received control message, the electrical device being capable of transmitting data to the controller device and the controller device being capable of transmitting data to the electrical device, the at least one electrical device comprising a memory device that stores a proxy that is a movable package comprised of a user interface software and a driver software, wherein the user interface software configures the user interface equipment of the controller device to provide a virtual user interface of the at least one electrical device, the driver software generating, in the controller device, the control message for carrying out actions on the at least one electrical device, on a basis of a control action given by a user through the virtual user interface of the at least one electrical device configured on the controller device, and - plural server devices having respective memory devices (151, 152, 251, 252, 253, 254) for storing data and relaying data traffic between the controller device and the at least one electrical device, each said memory device comprising a database storing the respective proxy of each electrical device connected to each of the server devices so that each proxy is stored in at least two distinct servers, the proxies being stored into nested hierarchical groups corresponding to child-parent relationships, with the electrical devices being children and each server being a parent of the child-parent relationships, - wherein the proxy of the at least one electrical device is retrievable from either of the at least two distinct servers upon receipt of a request message comprising the identifier of the controller device that identifies the controller device sending the request message from other controller devices. - a controller device (109, 209) comprising user interface equipment configurable with software, wherein the controller device is arranged to transmit a control message comprising an identifier of the controller device that identifies the controller device from other controller devices, - at least one electrical device (101, 102, 201, 202, 203, 204) comprising functional elements for carrying out actions defined by the received control message, the electrical device being capable of transmitting data to the controller device and the controller device being capable of transmitting data to the electrical device, the at least one electrical device comprising a memory device that stores a proxy that is a movable package comprised of a user interface software and a driver software, wherein the user interface software configures the user interface equipment of the controller device to provide a virtual user interface of the at least one electrical device, the driver software generating, in the controller device, the control message for carrying out actions on the at least one electrical device, on a basis of a control action given by a user through the virtual user interface of the at least one electrical device configured on the controller device, and wherein the user interface software configures the user interface equipment of the controller device to provide a virtual user interface of the at least one electrical device, the driver software generating, in the controller device, the control message for carrying out actions on the at least one electrical device, on a basis of a control action given by a user through the virtual user interface of the at least one electrical device configured on the controller device, and - plural server devices having respective memory devices (151, 152, 251, 252, 253, 254) for storing data and relaying data traffic between the controller device and the at least one electrical device, each said memory device comprising a database storing the respective proxy of each electrical device connected to each of the server devices so that each proxy is stored in at least two distinct servers, the proxies being stored into nested hierarchical groups corresponding to child-parent relationships, with the electrical devices being children and each server being a parent of the child-parent relationships, - wherein the proxy of the at least one electrical device is retrievable from either of the at least two distinct servers upon receipt of a request message comprising the identifier of the controller device that identifies the controller device sending the request message from other controller devices.