February 16, 2017

ElastiCon: An Elastic Distributed SDN Controller

  • Dixit A.
  • Hao F.
  • Kompella R.
  • Lakshman T.
  • Mukherjee S.

Software Defined Networking (SDN) has become a popular paradigm for centralized control in many modern networking scenarios such as data centers and cloud. For large data centers hosting many hundreds of thousands of servers, there are few thousands of switches that need to be managed in a centralized fashion, which cannot be done using a single controller node. Previous works have proposed distributed controller architectures to address scalability issues. A key limitation of these works, however, is that the mapping between a switch and a controller is statically configured, which may result in uneven load distribution among the controllers as traffic conditions change dynamically. To address this problem, we propose ElastiCon, an elastic distributed controller architecture in which the controller pool is dynamically grown or shrunk according to traffic conditions. To address the load imbalance caused due to spatial and temporal variations in the traffic conditions, ElastiCon automatically balances the load across controllers thus ensuring good performance at all times irrespective of the traffic dynamics. We propose a novel switch migration protocol for enabling such load shifting, which conforms with the Openflow standard. We further design the algorithms for controller load balancing and elasticity. We also build a prototype of ElastiCon and evaluate it extensively to demonstrate the efficacy of our design.

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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 ...