A new architecture of multiple private networks independent of optical line terminal (OLT) over Ethernet passive optical network (EPON) using ring topology is proposed. This architecture integrates the multiple private networks (PNs) with downstream/upstream EPON. Self determining private communications between optical network units (ONUs) are established using code-drop units. The use of optical code division multiple access (OCDMA) technique results in secure and reconfigurable PNs in the ring. Each ONU is assigned an appropriate codeword for private network communication and also the standard equipments for the up/downstream standard EPON communication. As an example, by using quadratic congruent (QC) codes with (p=5) leads to four optical private networks in the ring. To demonstrate the integration feasibility of multiple 622 Mb/s PNs over 1.25 Gb/s EPON using QC code-drop units, we analyze the network architecture by evaluating power budget, network dimensioning and BER performances.