摘要： This paper summarizes our studies on the software implementation of passive optical network (PON) physical-layer (PHY) processing to maximize the flexibility of the optical line terminal (OLT) in access systems, and demonstrates the softwarization of complete 10G-EPON upstream PHY of an optical system for the first time. Softwarization based on general-purpose hardware is more difficult to implement successfully than the application-specific integrated circuits (ASICs) used by dedicated hardware due to the marginal performance. Our work utilizes general-purpose graphic processing units (GPUs) as the implementation device as they offer significant computation performance. Our key advances that yield the softwarization of PON PHY processing, the GPU direct transfer technique and a low-complexity algorithm, are described. In addition, this paper describes the parallel implementation method of PON PHY decoding for upstream transmission. Demonstration results show that the proposed algorithm together with implementation satisfy the 10G-EPON standard by achieving 10.3125-Gbps real-time processing.