NeTS: Small: Exploiting Adaptive Protocols in Packet-Based Broadband Wireless Networks

隐藏信息传递的愿望自古以来就存在。这包括需要隐藏传输的存在；暴露传输的存在可能揭示发送者的位置，或者传输频率的增加可能表明事件即将发生。目前正在进行研究，以确定通信是否可以隐藏在当前和未来基于宽带分组的无线网络的射频辐射中。这些系统使用正交频分复用（OFDM）以及适应环境的协议，例如自适应调制和编码（AMC）、混合ARQ （HARQ）和机会调度。这项研究是基于无线系统中使用的协议的自适应特性使得网络容易被利用的关键见解。这项研究发现了这些弱点，并揭示了如何利用这些弱点通过隐蔽的自组织网络实现通信。理论系统分析与实验室原型相结合，定量地展示了隐蔽系统可以实现的信息传输和低概率检测能力，以及它们对目标无线系统性能的影响。这项工作可能会带来新的秘密通信技术。相反，暴露无线网络的漏洞有可能有助于指导新协议的创建或激励对现有技术的修改，使其不易被利用。

The desire to hide the transmission of information has existed since antiquity. This has included the need to conceal the very existence of transmissions; exposing the presence of transmissions may reveal the location of the sender or an increase in the frequency of transmissions may indicate the impending occurrence of an event. Research is underway to determine if communications can be hidden in the midst of the RF emissions of current and future broadband packet-based wireless networks. These systems use Orthogonal Frequency Division Multiplexing (OFDM) along with protocols that adapt to the environment, e.g., adaptive modulation and coding (AMC), Hybrid ARQ (HARQ), and opportunistic scheduling. This research is based on the key insight that the adaptive nature of the protocols used in wireless systems makes the networks vulnerable to exploitation. This research is discovering those weaknesses and exposing how those vulnerabilities can be used to enable communications by covert ad hoc networks. Theoretical systems analysis combined with laboratory prototyping is quantitatively demonstrating the information transfer and low probability of detection capabilities that covert systems can achieve as well as their impact on the performance of the target wireless system. The effort could lead to new covert communications techniques. Conversely, exposing the vulnerabilities of wireless networks has to potential to help to guide the creation of new protocols or motivate the modification of existing techniques to make them less susceptible to exploitation.