This Recommendation describes the functional requirements for radio over Internet protocol (RoIP) transmission systems based on data over cable service interface specifications (DOCSIS). The purpose of an RoIP system is to transmit data (DOCSIS based) over an upstream (US) radio frequency (RF) signal from a cable modem (CM) to a cable modem termination system (CMTS) through Internet protocol (IP) transmission in an optic-based cable television (TV) network.