February 17, 2017

Elastic Optical Interface with Variable Baud-Rate: Architecture and Proof-of-Concept

  • Belotti S.
  • Bigo S.
  • Dupas A.
  • Dutisseuil E.
  • Layec P.

Varying the symbol rate is an alternative or complementary approach to varying the modulation format or the channel spacing, in order to turn optical networks into elastic networks. We propose to allocate just-enough bandwidth for each optical connection by adjusting the symbol rate such that penalty originating from long cascades of optical filters is contained. This helps reducing over-provisioning for lightpaths where full capacity is not needed, by (i) eliminating unnecessary regenerators and (ii) reducing the power consumption of terminals, when the clock rate of electronics is reduced along with the Baud rate. We propose a novel architecture for an elastic optical interface combining a variable bitrate transceiver, paired with an elastic aggregation stage, with software-defined control. We then report a real-time FPGA-based prototype, delivering flexible transport frames to be sent with a PDM-QPSK modulation format. We interconnect this prototype with a commercial OTN switch and a centralized controller. We demonstrate fast and hitless reconfiguration of the interface and measure the reconfiguration time of hardware logic (<450µs) as well as end-to-end control and data plane (<0.9s).

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Recent Publications

March 23, 2017

Performance Comparison of Capacity-Achieving Modulation Formats for Transoceanic Optical Systems

  • Fernandez De Jauregui Ruiz I.
  • Ghazisaeidi A.
  • Tran P.

We experimentally compare the performance of geometrically-shaped (64APSK) and probabilistically-shaped 64QAM (PS64QAM) formats considering linear and nonlinear penalties.

March 20, 2017

LWIP and Wi-Fi Boost Link Management

  • K S.
  • Kim B.
  • Ling J.
  • Lopez-Perez D.
  • Ming Ding
  • Vasudevan S.

3GPP LWIP Release 13 technology and its prestandard version Wi-Fi Boost have recently emerged as an efficient LTE and Wi-Fi integration at the IP layer, allowing uplink on LTE and downlink on Wi-Fi. This solves all the contention problems of Wi-Fi and allows an optimum usage of the unlicensed band ...

March 13, 2017

Advanced C+L-Band Transoceanic Transmission Systems Based on Probabilistically-Shaped PDM-64QAM

  • Brindel P.
  • Buchali F.
  • Carbo Meseguer A.
  • Charlet G.
  • Fernandez I.
  • Ghazisaeidi A.
  • Hu Q.
  • Renaudier J.
  • Rios-Muller R.
  • Schmalen L.
  • Tran P.

We review the most recent, advanced concepts and methods employed in the cutting-edge spectrally-efficient coherent fiber-optic transoceanic transmission systems, such as probabilistic shaping, adaptive digital nonlinear compensation, rate-adaptive spatially-coupled low density parity check codes, and dual-band C+L-band transmission. Building upon all these concepts and methods, we demonstrate transmission of 179 ...