Exploiting Adaptive Protocols in Packet-Based Broadband Wireless Networks
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. |
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Sponsor: NSF CISE
This research involves experiments that will utilize real LTE-Advanced waveforms. Specifically, we are using the Agilent N5172B EXG X-series RF Vector Signal Generator and a new Agilent N5182A MXG RF Vector Signal Generator with the Agilent EEsof SystemVue RF System Design and Communications Architect software combined with a recently acquired Agilent N9030A Signal Analyzer and an older Agilent 8593E spectrum analyzer to create a realistic environment to address the research questions poses in this effort.
Hardware prototyping experiments will be constructed with one signal generator modeling the target signal, while the other signal generator will model the covert transmitter, using the N9030A signal analyzer as the target receiver. The associated SystemVue software enables the generation of LTE signals as well as complex waveforms as required by the proposed research. Also note that the SystemVue software includes a simulation capability with complex RF envelope carriers, RF effects, and throughput measurements that can be directly tied to these instruments. An older spectrum analyzer will be used as the intercept receive. This total environment creates a testbed for the experimental evaluation of system performance.
Questions?
Comments? Send mail to frost@ittc.ku.edu |