Ultimate Passive Optical Network (UPON)

正如《华尔街日报》最近所讨论的那样，互联网的巨大成功可能要归功于看不见的地下和海底光缆及其相关技术的巨大容量。事实上，20世纪90年代中期，随着第一个光学放大的跨大西洋电缆网络的出现，网络使用量的最初激增使得人们可以随时访问无法访问的信息。自1983年英国电信引入单模光纤网络以来，所有的发展都利用了相同的物理基础设施，在三十年的时间里实现了投资回报，容量增加了近五个数量级。然而，同样重要的是实际将客户连接到网络的“最后一英里”。虽然上个世纪的增长是由现有的铜线基础设施支撑的，但今天的网络在技术上更加分散，（按容量排序，从几kbit/s到几Gbit.s）这个传统网络，卫星分布（受延迟差的困扰）、无线网络、混合光纤/铜缆（例如BT Infinity）、同轴网络（有线电视）、无源光网络和点对点光网络。这些解决方案中的每一个都提供了适合当今市场的独特功能，使网络运营商（如BT，Virgin，EE）和服务提供商之间能够展开竞争。然而，除了基于光纤的解决方案外，进一步产能增长的潜力有限。随着对通信服务应用的需求在数量上持续增长（例如Twitter、YouTube、Facebook等），以及带宽（例如HDTV、4k视频.），承载该业务的通信系统的所有部分必须能够以越来越高的速度操作。不断增长的容量需求只能通过不断升级网络所有部分的容量来应对，包括主要城市之间的长途链路，以及在客户端或附近结束的关键“最后一英里”配电网络，这是该项目的重点。在UPON中，不是继续引入这一系列平台，每个平台都针对特定的应用和数据速率进行了优化，考虑到接入网本身的限制（由非线性和噪声之间的折衷引起）和核心网中实际可实现的容量，我们将识别允许每个用户（具有单个连接）的最大可能容量的网络配置。这种独特的方法将允许开发具有最高增长潜力的单一优化网络配置。通过将技术经济建模视为网络设计的基本组成部分，并与技术约束同等重要，还将确定，提出和演示具有成本效益的演进方案。这些方案将使网络容量和客户需求逐步推出，并在未来几十年开发带宽密集型应用程序。这将分三个阶段实现：实验和理论分析，地理布局对信号损失的影响，各种形式的光学失真的影响，最重要的是光强度改变光纤本身折射率的非线性失真，以及成本;开发新技术以提高每个客户可达到的数据速率，特别是利用一种新形式的光放大器的独特性能，即“光纤参量放大器”，以及专门为接入应用设计的新传输光纤;实验演示证明了UPON配置的可行性，并影响了主要网络运营商的决策过程。如果UPON成功，它将为人与人之间的最高连接铺平道路，以最佳成本提供前所未有的体验质量。

As recently discussed by the Wall Street Journal, the remarkable success of the internet may be attributed to the tremendous capacity of unseen underground and undersea optical cables and the associated technologies. Indeed, the initial surge in web usage in the mid-1990s coincides with the first optically amplified transatlantic cable network allowing ready access to information otherwise inaccessible. Tremendous progress has been made since then, and since the introduction of the single mode optical fibre network by BT in 1983 all developments have exploited the same physical infrastructure, enabling return on investment over three decades in time and almost five orders of magnitude in capacity. However, of equal importance have been the "last mile" actually connecting customers to the network. Whilst growth in the last century was supported by the existing copper infrastructure, todays networks are more technologically fractured, split between (in order of capacity, ranging from a few kbit/s to a few Gbit.s) this legacy network, satellite distribution (plagued by poor latency), wireless networks, hybrid fibre/copper (eg BT Infinity), coaxial networks (cable TV), passive optical networks and point to point optical networks. Each of these solutions offer unique features suited to today's market, enabling competition between network operators (eg BT, Virgin, EE) as well as service providers. However, with the exception of fibre based solutions the potential for further capacity growth is limited. As demand for communication services applications continue to grow in number (e.g. Twitter, YouTube, Facebook, etc.) and in bandwidth (e.g. HDTV, 4k video...), all parts of the communication systems carrying this traffic must be able to operate at higher and higher speeds. This ever-growing capacity demand can only be handled by continually upgrading the capacity of all parts of the network, including long-haul links between major cities, as well as the critical 'last mile' distribution networks ending at or near the customer premises which are the focus of this project.In UPON, rather than continuing to introduce this series of platforms, each optimised for a specific application and data rate, we will identify the network configuration which allows the maximum possible capacity per user (with a single connection), considering both the limitations of the access network itself (arising from trade-off between nonlinearity and noise) and the practically achievable capacity in the core network. This unique approach will allow the development of a single, optimised network configuration with the highest possible growth potential. By considering techno-economic modelling as a fundamental component of the network design, with equal weight to technological constraints, will also identify, propose and demonstrate cost effective evolution scenarios. These scenarios will enable the gradual roll out of network capacity and customer demand and bandwidth intensive applications are developed over the next decades. This will be achieved in three phases: Experimental and theoretical analysis, of the impact of geographical layout on the signal loss, of the impact of various forms of optical distortions - most importantly nonlinear distortions where the light intensity alters the refractive index of the fibre itself, and cost; Development of novel technologies to enhance the achievable data rates for each customer, specifically exploiting the unique properties of a new form of optical amplifier the "Fibre Optic Parametric Amplifier", and new transmission fibres specifically designed for access applications; Experimental demonstrations proving the feasibility of the UPON configuration and influencing the decision making processes within major network operators.If UPON is successful, it will pave the way for the highest possible connectivity between people, offering unprecedented quality of experience, at the optimum cost.