Xin Wang, PI
Most of the practical network protocols were designed based on sound yet ad-hoc heuristics. They have performed reasonably well as the Internet scaled up by six orders of magnitude. With the Internet continuing to grow, current protocols need to be re-engineered and optimized for emerging mobile applications.
Both engineering heuristics and optimization theoretic approaches were recently employed to enhance/re-engineer the existing network protocols. The resultant schemes, however, either cannot provide analytical performance guarantees, or are difficult to be deployed with the current Internet infrastructure. To fill the gap, this project aims to developing a systematic approach to design and analysis of readily deployable, scalable, yet optimal network schemes for mobile Internet applications. As core of the Internet protocols, the TCP performs window-based congestion control for competing data flows. Adopting queueing delay as the congestion measure, we reveal that TCP window-control mechanism amounts to implicit updates of source rates as “primal variables” and queueing delays as
“Lagrange dual variables” from optimization theoretic perspective. Confining to the design space of Internet, we then envision that the keys to cross-layer Internet optimization are development of non-standard window-control oriented implicit primal-dual solvers for underlying utility maximization problems, and design of jointly optimal network protocols as decomposition of such solvers.
Capitalizing on this original idea, we consider an Internet with wired backbone and a single access point that provides one-hop communications for mobile devices to access Internet. The proposed research will bridge the gap between the current network optimization theory and practical Internet designs, and is expected to benefit directly applications to next-generation Internet protocols and designs.
In an even broader sense, the proposed higher performance network schemes for mobile Internet applications will have an impact on society, if one takes into account how the Internet and wireless devices are expected to transcend various aspects of our everyday life.