Wireless Network Coding Dina Katabi, MIT Sachin Katti, University of California-Berkeley Abstract Network coding, i.e., having the routers mix packets' content, has recently attracted significant interest. Much theoretical work shows that network coding is optimal for multicast and improves throughput for unicast traffic. Emerging applications show how the theoretical results translate into practical gains in domains including peer-to-peer content delivery, anonymous communication, and switch design. Arguably, however, the most appealing domain for network coding is wireless networks, where recent advances have established network coding as an alternative design paradigm for wireless networks which delivers significant improvement in throughput and reliability. In only a couple of years, network coding has been integrated within the current network stack, proved to be an effective technique for opportunistic routing, shown robustness against Byzantine adversaries, and considered as a facilitator for mobile communication. Also, wireless network coding has been expanded from linear operations over packets to symbol-level network coding, a cross-layer approach that involves cooperation between two layers in the stack: the physical layer and the network layers. Finally, it has been further pushed all the way to the analog domain, introducing analog network coding, which operates over signals instead of bits. Wireless packet networks offer a natural setting for network coding because the very characteristics of wireless links that complicate routing, namely, their unreliability, broadcast nature, and interference, make coding a natural fit. For example, wireless networks exhibit high redundancy because a broadcast packet is heard by multiple nearby nodes. Network coding can exploit this redundancy to perform in-network compression of the data, thereby increasing the wireless throughput. Further, while interference has traditionally been considered harmful, network coding allows the nodes to exploit interference strategically, and perceive it as a special code which compresses the number of transmissions and improves throughput. This synergy between the characteristics of the wireless medium and network coding coupled with the fact that wireless networks are more amenable to innovative designs than their wired counterparts, opens up many opportunities for successful research. The tutorial will strive to point out how network coding simplifies wireless network design. It will walk the audience through the engineering process of applying network coding to wireless systems. The tutorial provides participants with the theoretical and practical knowledge necessary to understand the field of network coding, and also to conduct independent, innovative work in the area. Biographical Sketches --------------------- Dina Katabi is an Associate Professor in the Electrical Engineering and Computer Science department at MIT. She received her M.S. and Ph.D. degrees from MIT, in 1998 and 2003. Her work focuses on wireless networks, network security, routing, and distributed resource management. She has been awarded a the class of 1947 Career Development Chair in 2007, a Sloan Fellowship award in 2006, the NBX Career Development chair in 2006, and an NSF CAREER award in 2005. Her doctoral dissertation won an ACM Honorable Mention award and a Sprowls award for academic excellence. Sachin Katti has received his MS and PhD from MIT in 2005 and 2008 respectively. He has received his B.Tech. in electrical engineering from the Indian Institute of Technology, Bombay, in 2003 and a M.S. in computer science from MIT. His dissertation research focuses on redesigning wireless networks with network coding as the central unifying design paradigm. His work on practical network coding was published in SIGCOMM, NSDI, and other major networking conferences.