NeTS: Medium: Collaborative Research: Flexible All-Wireless Inter-Rack Fabric for Datacenters Using Free-Space Optics

数据中心是支撑我们社会的基础设施的关键部分。它们灵活地提供使基于互联网的经济得以实现的计算资源。设计强大的数据中心网络交换矩阵具有挑战性，因为它必须满足几个目标，即高性能、低设备和管理成本、增加新服务器的增量可扩展性，以及其他实际问题，如布线复杂性、电力和冷却成本。该项目设想并交付了一种与以前的架构截然不同的数据中心网络设计方法：使用自由空间光纤(FSO)通信链路的完全灵活的全无线交换矩阵，基本上使用激光束在空中无线传输数据。虽然室外FSO链路在恶劣天气条件下运行具有挑战性，但它们在温控数据中心环境中的使用在信息处理能力方面提供了巨大的和尚未开发的潜力。拟议的网络设计为每个服务器机架配备了多个FSO设备，每个设备都可以实时“操控”，以便与不同机架上的另一个FSO设备进行无线通信。转向能力使动态网络能够适应主流网络流量。该项目的成功将通过提高IT服务在几个关键经济部门的资本成本、运营费用和碳足迹方面的效率，产生明显的经济影响。该项目将把研究与教育结合起来，帮助学生成为数据中心网络行业的领域专家，并积极鼓励代表不足的少数群体和妇女参与。该项目解决了在上述拟议愿景的背景下出现的一些科学挑战。(I)该项目将开发具有成本效益的FSO设备，这些设备的外形因素很小，可以在细粒度的时间尺度上操纵。(2)此外，该项目还将制定可行的机制，以促进FSO链路的视线清晰，并解决实际操作挑战(例如，尘埃、振动)。(Iii)该项目将探索灵活网络拓扑设计的算法基础；(Iv)该项目将开发可扩展的网络管理解决方案，包括优化选择运行时拓扑和路由流量的算法；(V)在动态变化的拓扑中保证所需特性(例如，低拥塞和延迟)的机制；(Vi)最后，该项目将建立一个概念验证系统原型，并在适当的平台上进行广泛的评估。

Data centers are a critical piece of the infrastructure supporting our society. They flexibly supply the computing resources that enables the Internet-based economy. The design of a robust data center network fabric is challenging as it must satisfy several goals, viz., high performance, low equipment and management cost, incremental expandability to add new servers, and other practical concerns such as cabling complexity, and power and cooling costs. The project envisions and delivers on a datacenter network design approach that is radically different from prior architectures: a fully flexible, all-wireless fabric using Free-Space Optics (FSO) communication links, which essentially use laser beams to wirelessly transmit data through air. Although outdoor FSO links are challenging to operate under adverse weather conditions, their use in a temperature-controlled datacenter environments offers enormous and untapped potential in information-handling capacity. The proposed network design equips each rack of servers with a number of FSO devices, each of which can be "steered" in real-time to wirelessly communicate with another FSO device on a different rack. The steering ability enables a dynamic network that adapts to the prevailing network traffic. The project's success will have perceptible economic impact by making IT services more efficient - in terms of capital costs, operating expenses, and carbon footprint - across several critical sectors of the economy. The project will integrate the research with education to help students become domain experts in the datacenter networking industry, and actively encourage participation from under-represented minorities and women.The project addresses a number of scientific challenges that arise in the context of the above proposed vision. (i) The project will develop cost-effective FSO devices that have a small form-factor and can be steered at fine-grained timescales. (ii) In addition, the project will develop viable mechanisms to facilitate clear line-of-sight for the FSO links, and address practical operational challenges (e.g., dust, vibrations). (iii) The project will explore algorithmic foundations for the design of flexible network topologies; (iv) The project will develop scalable network management solutions including algorithms to optimally select a runtime topology and route traffic; (v) mechanisms to guarantee desired properties (e.g., low congestion and latency) in a dynamically changing topology; (vi) Finally, the project will build a proof-of-concept system prototype and conduct extensive evaluation on appropriate platforms.