Broadly, networking research has two flavors. First, ``system-design'' research is mainly about protocol and algorithmic design, implementation and experimentation. Second, ``network-theory'' research is mainly about performance analysis using mathematical tools. The research I enjoy most is a combination of these two, stemming from my desire to apply formal analytical and algorithmic methods to problems of high practical relevance, and propose solutions that can be implemented and used in practice.
Since I joined USC I have modeled and analyzed the performance of a variety of networks, including the Internet, mobile ad hoc networks, delay and disruptive tolerant networks, sensor networks, mesh networks, peer to peer networks and the web. I have also designed methods, algorithms, and protocols to solve problems related to such systems. For a more detailed presentation of my research work, see my publications and my research lab web site.