1. Dynamic Jamming Mitigation for Wireless Broadcast Networks Jerry T. Chiang Yih-Chun Hu 2007

2. Problem description What is Wireless communications? - inherently symmetric. - often susceptible to the jamming attack. - takes an attacker the same amount of power to modulate a signal. Many methods to Jamming Mitigation for wireless. - Spread spectrum. - Binary key tree. - Multiple-unicast system.

3. Related Work Spread spectrum A. J. Viterbi. CDMA Principles of Spread Spectrum Communication. Addison-Wesley, 1995. has long been used to resist jamming attacks in unicast environments. Tree keying scheme - Jerry T. Chiang Yih-Chun Hu (achieves asymmetry in a broadcast wireless network). Cut et al Try to detect and avoid jammed regions.

4. Solution approach Using Tree keying scheme: A.Types of Covers. B. Loss Due to Jamming Is Limited. C. Remerging Trees. What is Tree keying scheme? Achieves asymmetry in a broadcast wireless network. How to use Tree keying scheme? Use Tree Remerging Scheme. Fig 1 Fig 3 Fig 2

5. Dynamic Tree-remerging Scheme scales to number of receivers without increasing the number of codes in use, and uses fewer codes even in relatively small networks. Remerging Scheme no system can escape jamming without using at least j +1 codes. Analyzed False Alarms using both experimental and theoretical techniques. extensive analysis mitigated in a wireless broadcast network - These techniques will be even more promising in the future, as the use of Ultra-Wideband expands Evaluation

6. Tree keying scheme - Achieves asymmetry in a broadcast wireless network. - Best Spread Spectrum - demonstrated that false alarms can be reduced to -negligible levelsTheoretical Environment. - can be efficiently and effectively detected and a chip-accurate MATLAB simulation and an bit-accurate event-driven simulation in the ns-2 network simulator. conclusion

7. Thank You Questions?