ITR/ANI: Addressing Fundamental Issues for Robust Internet Performance

互联网在技术、管理和容量方面是庞大的、分散的和异构的。Internet成功的核心源于它对许多体系结构原则的遵守，其中的核心概念是网络应该努力实现一个健壮的、通常工作得相当好的性能水平。在各种情况下实现这一目标的主要技术之一是使Internet协议和机制具有适应性，以便它们能够自我调整，在任何情况下都能很好地工作。这种方法非常成功。然而，一些旨在在大范围条件下足够有效的机制，现在必须或将很快在超出其有效动态范围的制度中运行。例如，TCP拥塞控制机制需要重新访问未来的互联网，包括即将到来的高速路径和即将到来的低速路径（例如，有损无线链路）。类似地，体系结构优雅地容忍故障的能力不会扩展到新形式的故障，例如配置错误的路由信息或故障的中间件，也不会扩展到分布式压力，例如闪电人群、快速传播的蠕虫或拒绝服务（DoS）泛滥。如果我们将稳健性视为网络在各种条件下良好运行的能力，特别是在一个非常庞大、不断增长和不断变化的网络中，那么我们认为未来互联网的稳健性显然处于危险之中。在本提案中，我们强调了一种多方面的鲁棒性方法：1)在极端环境下的鲁棒性，例如非常高的速度和高度可变的延迟，这需要重新思考当今的拥塞控制机制。2)在出现新形式故障时的健壮性能，无论是在网络层，就健壮的路由而言，还是在应用层，就处理现在广泛部署的中间件而言，它们已经挤进了体系结构。这将需要研究更广泛的错误推理概念。3)在分布式压力存在下的稳健性能，包括恶意的（拒绝服务洪水；拥塞控制作弊者）和仅仅是拥挤的（闪电人群）。这将需要了解网络的拓扑结构和流量聚合的组成，以及部署在网络内部的新控制机制。实现这些目标的部分方法是改进现有的协议和机制，并研究新的协议和机制。但研究人员也强调通过检测早期故障来实现强大的性能，在短时间尺度上（通过分布式操作监控）和长时间尺度上（通过部署协议实现的诊断探测）。虽然这些主题肯定不能解决互联网架构面临的全部挑战，但它们确实解决了维护和增强互联网健壮性的一些核心问题。从某种意义上说，拟议的研究是保守的，因为我们根据当前互联网架构的工作来构建它，而不是提倡一种全新的方法。然而，研究人员认为，在某些方面，这种保守的方法使研究更基本而不是更少。“白纸”方法虽然更简洁，更有利于探索基本原理，但却忽略了一个至关重要的现实：一旦整合到一个真正的大规模网络中，不同的机制最终是如何相互作用的。

The Internet is large, decentralized, and heterogeneous in its technology, administration and capacity. The core of the Internet's success arises from its adherence to a number of architectural principles, central to which is the notion that the network should try to achieve a robust, very often works pretty well level of performance. One of the main techniques for achieving this across a wide range of conditions is making Internet protocols and mechanisms adaptive, so that they self-tune to work reasonably well in whatever circumstances they find themselves.This approach has been extremely successful. However, some of the mechanisms, designed to be good enough across a large range of conditions, must now or will soon operate in regimes beyond their effective dynamic range. For example, TCP congestion control mechanisms require revisiting for tomorrow's Internet, both the coming high speed paths, and the coming low speed paths (e.g., lossy wireless links). Similarly, the architecture's ability to gracefully tolerate failures does not extend to new forms of failures, such as misconfigured routing information or malfunctioning middle-boxes, nor to distributed stresses, such as flash crowds, rapidly-spreading worms, or denial-of-service (DoS) floods.If we view robustness as the ability of the network to function well over a wide spectrum of conditions particularly given a very large, ever-growing and ever-changing network then we argue that the robustness of the future Internet is clearly at risk. In this proposal, we emphasize a multifaceted approach to robustness:1) Robust performance in the presence of extreme environments such as very high speed and highly variable delay, which requires rethinking today's congestion control mechanisms.2) Robust performance in the presence of new forms of failure, both at the network layer, in terms of robust routing, and at the application layer, in terms of coping with the now widespread deployment of middleboxes that have elbowed their way into the architecture. This will require investigating broader notions of fault inference.3) Robust performance in the presence of distributed stresses, both malicious (denial-of-service floods; congestion control cheaters) and merely teeming (flash crowds). This will require an understanding of the network's topology and the makeup of traffic aggregates, coupled with new control mechanisms deployed inside the network.Part of the approach to these is to refine existing protocols and mechanisms, and investigate new ones. But the researchers also emphasize achieving robust performance by detecting incipient failures, on both short time scales (via distributed operational monitoring) and long time scales (via diagnostic probing of deployed protocol implementations).While certainly these topics do not address the full range of challenges facing the Internet architecture, they do address some of the core issues in preserving and enhancing the Internet's robustness. In one sense, the proposed research is conservative, in that we frame it in terms of working within the current Internet architecture, rather than advocating a clean sheet approach. The researchers argue, however, that in some ways this conservative approach makes for research that is more fundamental rather than less. The clean sheet approach, while more tidy and much more conducive to easy exploration of basic principles, misses the crucial reality of how different mechanisms wind up interacting once integrated into a truly large-scale network.