CAREER: Advances in Peer-to-Peer Networking

梅特卡夫定律指出，网络的“价值”随着用户数量的平方而增加。但对于大多数应用程序来说，随着参与者数量的增加，性能会下降，应用程序对用户的价值也会降低。集中式服务和应用程序架构面临的风险最大，因为它们无法在不断增加的用户群中保持性能。集中式站点可能代表处理瓶颈、单点故障或单点攻击。此外，单一服务器不能缓解第三方域中客户端糟糕的网络条件。复制和分布服务器是解决集中式体系结构问题的一种解决方案。点对点服务通过使用预先准备好并期望执行服务器的部分或全部功能的协作客户端来进一步分发。随着新的客户端给系统带来新的负载，他们也带来了新的资源。因此，点对点协作服务可以是一个强大的范例：如果平均而言，客户端带来了足够或超过足够的资源来平衡它们所产生的负载和成本，那么点对点服务可以随着参与者的数量而增加价值和性能。这项建议的主要目的是在理解和设计在对等环境中利用复制和协作的应用程序和服务方面取得根本性进展。在新学科中应用点对点技术的机会似乎是无限的。我建议使用点对点体系结构而不是集中式体系结构来研究几个只能实现或实现最佳性能的应用程序。这些新的对等应用包括匿名、安全自组织路由、可穿戴计算机的基于移动性的传输、防欺诈无服务器游戏和分布式信息检索。我们将研究的众多点对点应用都有共性：异类对等资源的存在，对等端提供的服务的冗余，以及应用数据和内容的复制。通过解决这些问题，研究人员将在发现和理解对等网络方面取得重要进展，并通过将这些结果应用于不同的问题领域，研究人员的工作将在安全(隐私、可用性和安全路由)、移动计算、可穿戴计算、多媒体和游戏以及分布式信息检索等领域产生更广泛的影响。研究人员提出的教育活动的主要主题是让本科生参与原创研究。该教育提案的目标是通过为本科生提供早期进行研究的机会，为他们进入研究生院做好准备。它包括一个可出版的本科生研究项目的综合计划，新的课程课程，开发网络和网络安全方面的实践实验练习，远程学习，以及少数民族宣传。通过将本科生的研究集中在这项提案的主题上，研究人员确保了一些好处。首先，这个教育部分的影响与我的研究目标紧密结合在一起。其次，通过与东北研究生教育和教授联盟(NEAGEP)主任协调努力，研究人员将通过准备和鼓励未被充分代表的少数族裔学生继续在马萨诸塞大学和其他大学攻读博士课程，来改善系内少数族裔的接触。第三，研究人员将通过提供新的三门课程的网络与安全课程来推进该系的教学任务。第四，研究人员将制作一套标准的网络和网络安全实践实验练习，供任何大学使用。最后，我的课程和实践练习的可用性，以及大学麻省理工学院现有的视频教学计划和躁狂远程学习计划，将增加课程的外部影响。

Metcalfe's law states that the "value" of a network increases with the square of the number of users.However, for most applications, as the number of participants increases, performance degrades, andso too does the value of application to the user. Centralized service and application architecturesare most at risk for not maintaining performance with an increasing user base. Centralized sites canrepresent a processing bottleneck, a single point of failure, or single point ofattack. Furthermore,a single server cannot mitigate for client's poor network conditions in third-party domains. Repli-cating and distributing servers is one solution for solving the problems of centralized architectures. Peer-to-peer services take distribution even further by using collaborative clients who are pre-pared and expected to perform some or all the functions of servers. As new clients bring new loadto the systems, they also bring new resources. Thus, peer-to-peer, collaborative services can be apowerful paradigm: if on average clients bring enough or more than enough resources to balancethe load and cost they incur, then peer-to-peer services can increase in value and performance withthe number of participants. The primary purpose of this proposal is to make fundamental advances in the understanding anddesign of applications and services that make use of replication and collaboration in a peer-to-peerenvironment. Opportunities for the application of peer-to-peer techniques in new disciplines seemlimitless. I propose to examine several applications that are only possible, or achieve their bestperformance, using peer-to-peer architectures and not centralized architectures. These include thenovel peer-to-peer applications of anonymity, secure ad-hoc routing, mobility-based transport forwearable computers, cheat-proof serverless gaming, and distributed information retrieval. There are commonalities to all the numerous peer-to-peer applications we will study: the ex-istence of heterogeneous peer resources, redundancy of offered services at peers, and replication ofapplication data and content. By addressing these issues, the researcher will make important advances in discovery and understanding of peer-to-peer networking and by applying those results to a diverse setof problem areas, the researcher's work will make a broader impact in in fields as diverse as security (privacy, availability, and secure routing), mobile computing, wearable computing, multimedia and gaming,and distributed information retrieval. The major theme of the researcher's proposed educational activities is the involvement of undergraduatesin original research. The goal of the educational proposal is to prepare undergraduate studentsfor graduate school by providing them with an early opportunity toperform research. It consistsof an integrated plan of publishable undergraduate research projects, new course curriculum, thedevelopment of practical lab exercises in networking and network security, distance learning, andminority outreach. By focusing the research of undergraduates on the themes of this proposal, the researcher is ensuring anumber of benefits. First, that the impact of this educational component is tightly integrated withmy research objectives. Second, by coordinating efforts with the director of the Northeast Alliancefor Graduate Education and the Professoriate (NEAGEP), the researcher will improve minority outreach inthe department by preparing and encouraging under-represented minority students to continue onfor doctoral programs at UMass and other universities. Third, the researcher will advance the department'steaching mission by providing a new three-course curriculum of networking and security. Fourth,the researcher will produce a standard set of practical laboratory exercises in networking and network security to be used at any university. Finally, the availability ofmy curriculum and practical exercises, aswell as UMass's existing Video Instruction Program and MANIC distance learning programs, willincrease the external impact of the curriculum.