A system and method for facilitating communication between a CMTS and an application sever in a cable network. Customer premises equipment (CPE) generates packets that are sent through a cable modem (CM) to a cable modem termination system (CMTS). A packet is parsed by CMTS and the destination IP address and port number compared to the destination IP addresses/port tuples received by the CMTS from a datastore. A packet that is directed to an IP address/port tuple on the target list (a “service request packet”) is modified to incorporate CMTS-identifying information and subscriber-identifying information in the packet header. When the application server communicates with the CMTS to reserve the network resources, the application server provides the CMTS the CM MAC and CM IP addresses to facilitate resource allocation, subscriber identification and billing.