Collaborative Research: CT-ISG: Secure Capacity of Wireless Networks

协作研究：CT-ISG：无线网络的安全容量过去十年见证了无线通信和网络应用的惊人增长。越来越多的用户仅仅依靠他们的无线通信和计算设备来传递敏感信息。保护无线传输信息的安全正变得越来越具有挑战性，但也是至关重要的。这一重要问题目前是在协议层次的较高层处理，但由于许多密码算法的安全性很难评估，并且在过去曾引起失望，因此迫切需要在物理层处理它。此外，人们对包括传感器节点和RF-ID标签在内的低复杂性发射器的大型网络越来越感兴趣，这些网络可能没有空间来容纳复杂和计算密集型的密码算法。迄今为止，对于低协议层的无线通信和网络，主要的设计目标一直是通过有效地应对无线信道的挑战和共享有限的无线资源来为尽可能多的用户提供高数据速率、可靠的通信。面向容量最大化的研究一直与信息传输的安全需求无关。同时，传输的信息的安全性已经在协议层次的上层处理，并且与底层网络的容量无关。该项目将无线网络设计中最重要的两个问题，即信息容量和信息安全结合在一起，揭示了两者之间的紧密耦合，旨在确定大容量和可证明安全的无线网络的设计原则，该项目采用信息论的方法，为无线网络的信息安全和信息可靠性提供保障。这项研究包括开发一个全面的无线网络设计框架，旨在实现所有用户的高容量和安全传输。考虑到各种恶意实体的存在和这些实体能够危害网络的各种级别，调查人员确定了以下基本研究方向：(I)建立无线网络基本构件的保密能力，即在智能窃听者存在的情况下可靠信息传输的最大速率；找到合法系统实体，即发送器和接收器，能够应对物理层安全威胁的方法；(Ii)确定友好节点之间的用户合作与转发信息的安全性和机密性之间的基本权衡；(3)重新讨论在存在安全威胁的情况下无线传输信道状态信息(CSI)的概念；确定这一广为接受的提高能力的概念可能造成安全漏洞的条件，并开发应对方法；(4)引入通过利用由于采用多天线(MIMO链路)而在通信信道中可用的自由度来保护网络的概念；(V)确定物理层对介质接入层和网络层的影响，并开发安全的跨层解决方案。该项目的结果将有助于确定各种无线网络的容量与安全之间的基本设计权衡，并将为未来的无线通信系统达到安全容量极限提供设计原则。该项目是宾夕法尼亚州立大学PI和马里兰大学PI之间的合作成果。

Collaborative Research: CT-ISG: Secure Capacity of Wireless NetworksThe last decade has witnessed an amazing growth in wireless communications and networking applications. More and more subscribers are relying solely on their wireless communication and computing devices for communicating sensitive information. Preserving the security of wirelessly transmitted information is becoming ever more challenging, yet essential. This important issue is currently dealt with at the higher layers of the protocol hierarchies, yet the need to deal with it in physical layer is imminent as the security of many cryptographic algorithms is hard to evaluate and has caused disappointment in the past. In addition, there is rising interest in large networks of low-complexity transmitters including sensor nodes and RF-ID tags that may not have room for complicated and computationally intensive cryptographic algorithms.The main design goal up to date, for wireless communications and networking at the lower protocol layers, has been to provide high data rate, reliable communication to as many users as possible, by efficiently dealing with the challenges of the radio channel and sharing limited wireless resources. Capacity maximization oriented research has been agnostic to the security requirements of information transmitted. At the same time, security of the information transmitted has been dealt with at the upper layers of the protocol hierarchy, and has been agnostic to the capacity of the underlying network. This project brings together the two most important issues in wireless network design, i.e., information capacity and information security, exposing the tight coupling between the two, and aims to identify design principles for high-capacity and provably-secure wireless networks.This project takes an information theoretic approach to provide guarantees on information security and information reliability for wireless networks. The research includes the development of a comprehensive wireless network design framework that aims at achieving high capacity and secure transmission for all users. Accounting for the existence of a variety of malicious entities and a variety of levels at which these entities are capable to harm the network, the investigators identify the following fundamental research directions: (i) establishing the secrecy capacity of fundamental building blocks of wireless networks, i.e., the maximum rate of reliable information transmission in the presence of intelligent eavesdroppers; finding ways in which the legitimate system entities, i.e., transmitters and receivers, can cope with the security threats at the physical layer; (ii) identifying the fundamental tradeoffs between user cooperation between friendly nodes and the security and the confidentiality of relayed information; (iii) revisiting the notion of wirelessly transmitting channel state information (CSI) in the presence of security threats; identifying conditions under which this well-accepted notion to improve capacity may create security vulnerabilities, and developing methods to deal with this; (iv) introducing the notion of securing the network by utilizing the degrees of freedom in the communication channel available as a result of employing multiple antennas (MIMO links); (v) identifying the impact of the physical layer on the medium access and networking layers and developing secure cross-layer solutions.The results of this project will help identify fundamental design trade-offs for capacity versus security for a variety of wireless networks, and will provide design principles for future wireless communication systems achieving the secure capacity limits. The project is a collaborative effort between the PI at Penn State and the PI at University of Maryland.