A gateway receives network presence information regarding a mobile
station. The network presence information is based, at least in part, on
status messages that a network access server, such as a packet data
serving node (PDSN), sends, for example, to an accounting server. The
network presence information identifies the mobile station, such as by
Internet Protocol (IP) address, network access identifier (NAI), and/or
mobile directory number (MDN). When the gateway receives a request from a
mobile station to access a content server, e.g., an HTTP GET request, the
gateway inserts identifying information, such as NAI and/or MDN, into the
request to identify the mobile station to the content server.