Advanced passive optical network architecture and scheduling algorithm provisioning dynamic bandwidth for local customer internetworking

Abstract

Recently, increase of various application programs which are based on Internet has brought about a large growth in population of Internet use, increment of required bandwidth, and improvement of quality. Therefore, to construct optical subscriber network is necessary between high speed backbone network and user to provide broadband service and supply the demand for Internet economically and efficiently for subscribers. Passive optical network (PON) which is expected optical subscriber transmission technology in the next generation is becoming the center of interest for satisfying some requirements. PON is considered as a cost-effective solution of the bottleneck problem in the access network. PONs are also attractive due to the reduced number of fibers connecting the central office (CO) and the end-user, and the economical number of optical devices, which brings directly or indirectly savings. In PON, all communications are performed between an optical line terminal (OLT) and optical network units (ONUs). In particular, local data from ONUs also generated with many subscribers. The local data is customer data which is originated from one subscriber to be delivered to all or some subscribers within the same PON. Moreover, communication between ONUs serviced by one OLT is also emerging network service among various PON service. Therefore, customers need inter-communication capability among themselves for various application programs and telecommunication services, such as teleconferencing or information broadcasting. According to increase of the number of subscribers connected with ONU, it is a necessary additional function in fiber-to-the-building (FTTB) or fiber-to-the-node (FTTN) based on wide coverage. However, this shared LAN emulation function in OLT uses a portion of upstream and downstream channel to transmit the local data, so bandwidth for existing broadband service becomes reduced. The OLT is also complicated because of being processing and buffer sc...