Network error control for Rapid and Reliable Data Delivery (R2D2)

广泛期待的第四代（4G）移动的通信预计将适应高度流行但带宽要求高的移动内容，范围从高清晰度多媒体流和在线视频游戏到软件分发和电影下载。作为4G网络的主导系统的长期演进（LTE）已经引入了最先进的喷泉编码来支持数据广播和多播服务。喷泉码的吸引人的属性，以适应传输速率的信道条件，无论接收移动的用户的数量，然而，受到限制的延迟和网络开销之间的权衡。因此，内容流传输对低延迟的固有要求可能导致开销的显著增加，如最近的研究所表明的，如果相邻的移动的节点形成协作集群，则可以减轻开销。更具体地说，配备了WiFi或蓝牙等短距离通信功能的4G设备可以向相邻设备请求丢失的数据包。在每个协作簇中使用网络编码可以进一步减少流量和能量消耗。因此，在应用层的点对多点喷泉编码和协作网络编码与在物理层的点到点信道编码的组合是传统的自动重传请求（ARQ）协议的有吸引力的替代设计，其可以是能量和带宽效率较低的。尽管如此，仍有很大的空间来使所提出的方案适应即将到来的4G宽带技术的要求，并开发全新的范例来满足下一代网络通信中对高质量媒体的流式传输和下载的日益增长的需求。拟议项目旨在开发一个数学框架，以确定各种网络参数之间的关键关系，有助于理解网络动态，并协助网络编码架构的系统级优化。如果信道编码和网络编码的单独设计被内容分发的联合设计所取代，那么低级优化的好处也将得到利用，这将更好地利用冗余的好处并提高可靠性，而无需对现有基础设施进行重大更改。该项目还希望深入研究新兴的网络纠错研究领域，并开发统一信道和网络代码的实际实现，这些代码具有高可靠性，低解码复杂性和增加恶意用户的安全性。拟议的研究将与来自葡萄牙和挪威大学的国际合作者协商进行，其成果不仅将有利于移动的ad-hoc架构，还包括相关系统，例如宽带固定无线接入网络、机器对机器通信以及图像和视频处理。我们预计，我们的网络差错控制技术的工作将有助于加强英国的研究基地，并发挥重要作用，把英国在发展的最前沿，在下一代移动的技术的竞技场。

The widely anticipated fourth generation (4G) of mobile communications is expected to accommodate highly popular but bandwidth-demanding content on-the-move, ranging from high-definition multimedia streaming and online video gaming to software distribution and movie downloads. Long-Term Evolution (LTE), which is the dominant system for 4G networks, has introduced state-of-the-art fountain coding to support data broadcast and multicast services. The appealing property of fountain codes to adapt transmission rate to channel conditions, regardless of the number of receiving mobile users, is however constrained by a trade-off between latency and network overhead. The inherent requirement of content streaming for low latency can thus lead to a significant increase in overhead which, as recent research suggests, can be alleviated if adjacent mobile nodes form cooperative clusters. More specifically, 4G-enabled devices equipped with short-range communication capabilities, such as WiFi or Bluetooth, could request missing packets from neighbouring devices. The use of network coding in each cooperative cluster could further reduce traffic and energy consumption. Therefore, the combination of point-to-multipoint fountain coding and collaborative network coding at the application layer with point-to-point channel coding at the physical layer is an attractive alternative design to conventional automatic repeat request (ARQ) protocols, which can be less energy and bandwidth efficient. Nevertheless, there is great scope for tailoring the proposed scheme to the requirements of upcoming 4G broadband technologies and developing radically new paradigms to satisfy the increasing demand for streaming and downloading of high quality media in next generation networks communications. The proposed project aims to develop a mathematical framework to identify key relationships between the various network parameters, contribute to the understanding of network dynamics and assist in the system-level optimisation of network-coded architectures. The benefits of low-level optimisation will also be harnessed if separate designs of channel coding and network coding are replaced by joint designs for content distribution, which better leverage the benefits of redundancy and boost reliability without requiring significant changes to existing infrastructures. The project also aspires to delve into the emerging research field of network error correction and develop practical implementations of unified channel and network codes that deliver high reliability, low decoding complexity and increased security from malicious users.The proposed research will be carried out in consultation with international collaborators from universities in Portugal and Norway and its outcomes will benefit not only mobile ad-hoc architectures, but related systems too, such as broadband fixed wireless access networks, machine-to-machine communications and image & video processing. We anticipate that our work on network error control techniques will contribute to the reinforcement of the UK research base and play an important role in putting the UK at the forefront of developments in the arena of next-generation mobile technology.