CSR: Medium: Collaborative Research: Foundations of Cache Network Operations for Content Delivery

当用户上网阅读新闻、观看视频、购买产品、玩游戏或使用社交网络时，用户访问的内容通过称为内容分发网络(CDN)的大型互联网规模的网络分发到他/她的设备。CDN可能由分布在全球数千个数据中心的数十万台服务器组成。由于流量的巨大规模和多样性，以及其庞大的分布式服务器基础设施，运营大型CDN是具有挑战性的。本研究致力于实现CDN的高效运营，其核心目标是最大限度地降低运营成本，最大限度地提高网络的健壮性。该项目开发了将不同流量类别映射到服务器的技术，以优化资源使用、提高命中率并降低带宽成本。该项目还开发了自适应和自调优系统，该系统对常见的CDN可变性来源具有健壮性，包括对象流行度/大小、负载、延迟和可用性。由于CDN是支持网络、视频和其他在线应用的关键基础设施，该项目对互联网用户的体验质量产生了重大的积极影响，同时降低了互联网服务的成本。该项目将通过让本科生参与研究来扩大参与范围。此外，该项目将通过外展活动帮助吸引女性从事科学、技术、工程和数学(STEM)职业，包括为中学女孩举办的“科技之夜”和“路演”，以及为从高中到研究生院的学生举办半年一次的“职业建议讲座”。该项目还将在课程中包含有关大规模网络运营的主题。最后，该项目将通过整合我们对生产系统的研究，并使学生能够通过实习获得CDN行业的实际经验，在CDN行业的推广和技术转移方面投入大量资金。该项目的所有产品，包括研究论文、软件和数据，都将向公众开放。特别是，该项目产生的软件和数据将被存档至少五年，如果可行，甚至更长时间。将有两个软件和数据存储库：一个在马萨诸塞州大学阿默斯特分校，另一个在(https://www.cs.umass.edu/~ramesh/Site/CODE_DATA.html)(http://www.cs.cmu.edu/~harchol/SoftwareDataRepository.html).This，这反映了国家科学基金会的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

When a user goes online to read the news, watch videos, buy products, play games, or use a social network, the content accessed by the user is delivered to his/her device by a large Internet-scale network called a content delivery network (CDN). A CDN may consist of hundreds of thousands of servers located in thousands of data centers around the world. Operating a large CDN is challenging due to the sheer scale and diversity of the traffic and due to the vastness of their distributed server infrastructure. This research focuses on enabling highly efficient CDN operations.The key goals of this project are minimizing the operating cost and maximizing the robustness of the network. This project develops techniques for mapping different traffic classes to servers, so as to optimize resource usage, increase hit rates, and lower bandwidth costs. This project also develops adaptive and self-tuning systems that are robust to common sources of CDN variability, including object popularity/size, load, latency, and availability. Since CDNs are the key infrastructure enabling web, video, and other online applications, this project has a significant positive impact on the quality-of-experience of Internet users, while lowering the cost of Internet services.The project will broaden participation by involving undergraduates in the research. Further, the project will help attract women to Science, Technology, Engineering, and Mathematics (STEM) careers through outreach activities, including "Tech Nights" and "Roadshows" for middle school girls, and including semi-annual "Career Advice talks" to students from high school through grad school. The project will also incorporate topics in large-scale network operations in the curriculum. Finally, the project will invest significantly in outreach and tech transfer to the CDN industry by incorporating our research in production systems and enabling students to gain real-world experience in the CDN industry through internships.All products of the project, including research papers, software, and data, will be made available to the public. In particular, the software and data produced by the project will be archived for at least five years, and even longer when feasible. There will be two software and data repositories: one at UMass Amherst (https://www.cs.umass.edu/~ramesh/Site/CODE_DATA.html) and the other at CMU (http://www.cs.cmu.edu/~harchol/SoftwareDataRepository.html).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.