March 01, 2019

Capacity Scaling of Wireless Networks: Protocol Limited or Model Limited?

  • Du J.

Given a large wireless network deployed within an area, where each node wants to transmit to a random destination node within the network at some given rate, how fast can the sum rate grow as the number of nodes scales up? Previous work have shown that, multi-hop routing provides a scaling at most as the square root of network size, whereas hierarchical cooperation protocols have the potential to support linear scaling by creating virtual MIMO transmission between clusters of nodes. In this talk, we will show some new capacity scaling bounds by accounting for the constraints of local communication. Our upper bound is significantly smaller than previous known bounds for networks of any reasonable size (e.g., N<10^40). On the other hand, we realized that the model of capacity scaling, originally posed by Gupta and Kumar and inherited by all the follow up work, has an intrinsic bottleneck. It assumes equal rate for all source-destination pairs, which effectively allocates more resource/time to pairs with worse channel quality. Could such artificial enforcement of equal message size impose the ultimate limit on capacity scaling?

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Recent Publications

January 01, 2019

Friendly, appealing or both? Characterising user experience in sponsored search landing pages

  • Bron M.
  • Chute M.
  • Evans H.
  • Lalmas M.
  • Redi M.
  • Silvestri F.

© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Many of today's websites have recognised the importance of mobile friendly pages to keep users engaged and to provide a satisfying user experience. However, next to the experience provided by the sites themselves, ...

January 01, 2019

Analyzing uber's ride-sharing economy

  • Aiello L.
  • Djuric N.
  • Grbovic M.
  • Kooti F.
  • Lerman K.
  • Radosavljevic V.

© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Uber is a popular ride-sharing application that matches people who need a ride (or riders) with drivers who are willing to provide it using their personal vehicles. Despite its growing popularity, there exist ...

January 01, 2019

The paradigm-shift of social spambots: Evidence, theories, and tools for the arms race

  • Cresci S.
  • Petrocchi M.
  • Pietro R.
  • Spognardi A.
  • Tesconi M.

© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Recent studies in social media spam and automation provide anecdotal argumentation of the rise of a new generation of spambots, so-called social spambots. Here, for the first time, we extensively study this novel ...