January 01, 2018

QoS-aware protection in flexgrid optical networks

Elastic optical networks generally rely on protection and restoration mechanisms to prevent the detrimental effect of fiber cuts. In particular, we investigate optical protection in flexgrid optical networks where the symbol rate is varied as a complementary approach to modulation format. We propose a novel protection scenario, whereby premium traffic survives cuts with just-enough bandwidth, which we call ""quality-of-service-aware protection"" (QoS-aware protection). The proposed mechanism exploits a variable baud rate transponder in order to reduce the spectrum occupancy of the protecting path and to ease the establishment of new traffic demands. Equipped with two lasers and optical switches, the QoS-aware node allows fast switching between different working and protecting bit rates. The two wavelengths also help to reduce the spectrum fragmentation. We compute typical spectral usage boosted by 80% to protect 25% of premium traffic with respect to current 1 + 1 protection. We demonstrate a field programmable gate array (FPGA)-based proof-of-concept node of QoS-aware protection that reconfigures in <2.8 ms. We program and select the ratio of premium versus best effort traffic as a tunable input parameter of the proof-of-concept.

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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 ...