Ethernet Passive Optical Network (EPON) systems have been successfully deployed worldwide for high-speed access networks. EPON uses the 802.3 Ethernet MAC over optical fiber to provide high-speed IP connectivity to the home or business. In November 20111, the IEEE 802.3 formed a study group  to study the feasibility of creating a coax cable physical layer (PHY) for the EPON MAC. With the Ethernet-Protocol-over-Coax (EPoC) PHY, cable operators can deploy high speed IP connectivity using the EPON MAC over optical fiber or coaxial cable. Key criteria for selecting and evaluating a PHY layer will be the application in which it is used and the MAC performance over the system. The MAC layer performance over a Coax PHY layer will be different than an optical fiber PHY layer. Emerging interactive services and higher speed data links will require shorter delays than today’s services over low speed links. In this paper, the bandwidth, buffering requirements, and delay over an EPOC network will be predicted for different deployment scenarios and physical layer technologies for the EPOC PHY. The impact of increasing the round trip delay will be considered in a comparison between EPON and EPOC with expected services requirements.