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The passive optical network (PON) is widely deployed in access networks, and various specifications have become standards designed to meet demands of each market. To accelerate new PON-based service creation, software-defined network enabled broadband access (SEBA) is being studied; it uses a common API to abstract various optical line terminal (OLT)/optical network units (ONUs) and manages the devices via a controller. However, the current abstraction unit in SEBA supports only ITU-T PON. In order to support IEEE PON, multiple package types and switching management functions must be considered. This paper proposes a technology profile including package types for IEEE specification and an adapter that abstracts IEEE PON and switches functions according to the specified package type. The logical link configuration settings for ITU-T PON and IEEE PON are implemented in common, and the adapter abstracts IEEE PON OLT/ONU by switching between extended operation, administration, maintenance (eOAM) functions for package B and other eOAMs. We demonstrate the proposed software on a system implemented using commercially available OLT/ONU and OSS in SEBA. The results show that OLT/ONUs can be managed via a common API, differences in package types can be abstracted by technology profiles and our adapter, and that a common SEBA platform can manage, in a unified manner, both ITU-T PON and IEEE PON.

A time division multiplexing-passive optical network (TDM-PON) has been attracting attention with a view to realizing the cost-effective mobile fronthaul (MFH) of a mobile base station (BS). A cost-effective MFH is needed because a lot of BSs will be densely deployed in fifth generation mobile networks (5G). A TDM-PON is capable of reducing the network cost as the number of subscribers increases. However, the number of remote radio heads that can be accommodated in a TDM-PON is limited since a 5G MFH has a throughput of more than 1 Gbps. The accommodation of not only the MFH but also multiple services will enable us to construct a more cost-effective network that will in turn achieve cost-effective 5G MFH. Therefore, we propose the accommodation of the fronthaul and secondary services in a TDM-PON. Our proposed TDM-PON allows us to increase the number of accommodated ONUs. We use a traffic monitor to capture the MFH signal and then estimate the unallocated interval in the PON domain by using the characteristics of the MFH signal. The signals of the secondary services are inserted in the unallocated interval of the MFH signal. We estimate the unallocated interval by using this characteristic. In this paper, we report experimental and the theoretical results for our proposed technique obtained with a 10 Gigabit-Ethernet PON prototype. Moreover, we also discuss the variation in throughput when we increase the number of ONUs.

Dense deployment of many small cells is one promising solution to cope with mobile traffic increases. However, the deployment needs many optical fibers and network operators require efficient management for these cells. To overcome these issues, we have proposed a WDM-PON system managed by an electrically embedded pilot tone and confirmed its feasibility. In this letter, we compare management methods and clarify 128-kb/s pilot tone parameters that negligibly affect LTE signals transported by CPRI option seven experimentally. The results show that the modulation index as high as 20% and carrier frequency as high as 5 MHz are suitable under 1.0-dB optical power penalty.

A wavelength-division-multiplexing (WDM) access system can be used in two basic ways: user multiplexing, which assigns a wavelength to each user, and service multiplexing, which assigns a wavelength to each service. In current designs for service multiplexing, each optical network unit (ONU) must have a demultiplexer that can select any wavelength. This paper proposes a new WDM access system that uses one demultiplexer shared by many ONUs to offer optical-distribution access services. This system realizes significant cost reductions due to its passive optical network (PON) architecture, high capacity due to its WDM technology, and easy wiring through the use of multimode fiber (MMF). As one of the realization approaches of the shared demultiplexer, we explain the principle and configuration of a shared demultiplexer based on diffraction theory, and present theoretical and experimental analyses of a prototype 4/spl times/(4/spl times/4) shared demultiplexer whose configuration is based on Littrow mounting. Experimental transmission performances demonstrate the feasibility of the proposed WDM access system.