System and method embodiments are provided for asynchronous event notification and message handling in dynamic adaptive streaming over hypertext transfer protocol (DASH). The embodiments includes sending in a segment file, from a network server to a client, a message box that is configurable for encryption, for scheduling a callback from the client, and with one or more arguments according to a messaging scheme of the message box. The network server further sends a message handling descriptor to the client for reloading a media presentation description (MPD) for obtaining a DASH event. The client then configures a universal resource locator (URL) for the MPD using the message box and the message handling descriptor, and sends the URL back to the network server. After receiving the URL, the network server sends the MPD to the client, which then uses the MPD to request segments of an asynchronous event.