Abstract

Our talk discusses strategies to reduce congestion in wireless networks and is motivated by the following two observations. Given the performance of existing wireless networks, 5G is expected to experience resource scarcity and hence congestion in the backhauling and in the wireless part. This may create delays to the real-time traffic originating from interactive applications and web browsing. Also, a significant fraction of the 5G traffic is expected to be generated by applications that are characterized by some delay-tolerance (such as the offline video launched recently by Netflix, the material posting at the social networks and the cache updates for content prefetching at the base stations). This delay tolerance is usually restricted and does not allow for complete time-scale decomposition of the traffic (e.g., shifting delay-tolerant transfers during the night). Still, it creates a rich space of potential improvement both in technical and economic terms, by smoothing out traffic peaks. A reasonable suggestion is to treat delay-tolerant traffic with lower priority compared to the real-time one, by employing Lower than Best Effort Protocols at the transport layer (Ledbat, TCP-LP). Our research findings suggest that this approach not only lacks any adoption incentives in the form of performance guarantees for the affected traffic but may also have negative effects on the delay-sensitive traffic, which we like to protect. We propose an application layer congestion control algorithm to be implemented at the server side, which strives to cause the least possible harm on real-time flows traversing the same link, while providing some necessary performance guarantees to the delay-tolerant traffic to make it stable. Finally, we propose two adoption alternatives, where the network provider may incentivize the content providers by applying transit-like charges at the interconnection points or may implement the algorithms at its own servers after classifying the traffic according to its priority. 

Biography

Prof. Costas A Courcoubetis was born in Athens, Greece and received his Diploma (1977) from the National Technical University of Athens, Greece, in Electrical and Mechanical Engineering, his MS (1980) and PhD (1982) from the University of California, Berkeley, in Electrical Engineering and Computer Science. He was MTS at the Mathematics Research Centre, Bell Laboratories, Professor in the Computer Science Department at the University of Crete, Professor in the Department of Informatics at the Athens University of Economics and Business, and since 2013 Professor in the ESD Pillar, Singapore University of Technology and Design where he heads the Initiative for the Sharing Economy and co-directs the new ST-SUTD Centre for Smart Systems. His current research interests are economics and performance analysis of networks and internet technologies, sharing economy and mobility, regulation policy, smart grids and energy systems, resource sharing and auctions.  Besides leading a large number of research projects in these areas he has also published over 100 papers in scientific journals such as Management Science, Operations Research, Mathematics of Operations Research, Journal on Applied Probability, ToN, IEEE Transactions in Communications, IEEE JSAC, SIAM Journal on Computing, etc. and in conferences such as FOCS, STOC, LICS, INFOCOM. GLOBCOM, ITC, ACM SIGMETRICS. His work has 14,000 citations according to Google Scholar. He is co-author with Richard Weber of “Pricing Communication Networks: Economics, Technology and Modelling” (Wiley, 2003).