A server application executing on the public Internet may establish or re-establish a packet data network (PDN) connection with a client application executing on mobile device over a cellular network by initiating a telephone call to the mobile device via a cellular access network node according to a telephone number associated with the client application. The mobile device may receive a paging for the telephone call from the cellular access network node. In response to the paging, the mobile device may determine a PDN communication channel associated with the server application, the PDN including the cellular access network node, and send a set of data to the server application via the determined PDN communication channel. The server application may, in response to receiving the set of data, send a second data set of data to the client application over a PDN communication channel associated with the client application.