An example method, for implementation by an example notification system, comprises creating a TCP connection between a client device and a cloud device; sending, by the cloud device, a first UDP message to the client device; and waiting, by the client device, to receive the first UDP message until a predetermined time after the creation of the TCP connection. If the client device has not received the first UDP message by the predetermined time, the method comprises sending, by the client device, a second UDP message to the cloud device, wherein sending the second UDP message starts an open time period during which the client device is able to receive UDP messages from the cloud device.