NeTS-NBD: Network Coding-Based Protection

网络生存性是网络运营商必须提供的一项重要要求。一般来说，生存性技术试图实现两个目标，即增加(a)检测故障并从故障中恢复的灵活性和(b)资源效率。然而，这两个目标在大多数情况下是相互矛盾的，很难同时实现。这主要是因为敏捷性需要使用昂贵的预先配置的保护电路，而工作连接不能使用这些电路。在本项目中，网络编码将用于提供保护，作为实现满足上述两个目标的可生存网络运行的手段。特别是，预先配置的保护电路将由多个连接共享，其中所有这些连接同时在共享电路上传输其信号。网络编码，信号在传输前进行组合，避免了信号之间的争用和冲突，同时提供了信号的备份副本，这样如果发生故障，可以很容易地从组合信号中立即提取信号。本课题的目的是建立网络编码的理论和技术，通过保护来支持可生存的网络运行。在严格阐述了网络编码下的网络生存性问题后，提出了单链路故障下使用网络编码进行网络保护的理论。然后，该理论将被扩展到处理多链路和/或节点故障的情况。对于特定类型的网络连接，将开发更强的结果。然后，该理论将应用于开发基于有线和无线网络的网络编码保护的实施策略，在不同层使用不同的协议。本课题的智力优势在于，将为使用网络编码以敏捷、资源高效的方式支持保护提供理论基础，并将介绍基于网络编码的保护的实现方法。这项研究的更广泛的影响是，它将为基于网络编码的生存能力提供一个总体方法，这将扩展并应用于几个网络环境。pi期望网络设备制造商将考虑开发的技术用于他们的设备，网络运营商将考虑在他们的网络中使用，因为这种方法将提供成本效率、敏捷性和灵活性。该计划也将训练研究生在一个新的研究领域，以及探索网络编码新技术的新应用。

Network survivability is an important requirement that must be provided by network operators. In general, survivability techniques attempt to achieve two objectives, namely increasing (a) the agility of detecting and recovering from failure and (b) resource efficiency. However, these two objectives are in most cases contradictory and are difficult to achieve simultaneously. This is mainly because agility requires the use of expensive pre-provisioned protection circuits, which cannot be used by working connections.In this project, network coding will be used to provide protection as a means of achieving survivable network operation that satisfies the above two objectives. In particular, pre-provisioned protection circuits will be shared by multiple connections where all such connections transmit their signals simultaneously and on the shared circuits. Network coding, where signals are combined before transmission, avoids the contention and collision between the signals, while simultaneously providing backup copies of the signals such that if failures take place, the signals can be easily and instantaneously extracted from the combined signals. The purpose of this project is to establish the theory and techniques for using network coding to support survivable network operation through protection. After rigorously formulating the problem of network survivability under network coding, a theory for network protection using network coding under single link failures will be introduced. The theory will then be extended to also handle the cases of multiple link and/or node failures. Stronger results for specific types of network connections will be developed. The theory will then be applied to develop implementation strategies for network coding-based protection for wireline and wireless networks, using different protocols at different layers.The intellectual merit of this project is that it will provide the theoretical bases for the use of network coding to support protection in an agile, and resource efficient way, and will also introduce implementation methods for network coding-based protection. The broader impact of this research is that it will provide an overarching approach for network coding-based survivability, which will extend and apply to several networking environments. The PIs expect that the developed techniques will be considered by network equipment manufacturers for adoption in their equipment and by the network operators for use in their networks, as this approach will provide cost efficiency, agility and flexibility. The project will also train graduate students in a new area of research, and in exploring novel applications of the new technique of network coding.