Abstract

Distributed control solutions were introduced to address controller reliability and scalability issues in software-defined networking. The dynamic nature of network traffic can lead to load imbalance amongst controller instances. A highly loaded controller instance can be slower in responding to datapath queries, and can slow down the entire control platform as state synchronization, and consensus amongst controller instances are performed cooperatively.

In this talk, we present new and efficient load migration protocols for shifting input load associated with overloaded controller instances towards lightly loaded instances. These protocols can be used for a wide range of network applications including load balancing, power saving, and resource optimization. Unlike previous protocols for load migration, our solutions are resilient to failures during migration, and ensure consistency among all controller instances. The protocols are also more efficient, with 25-55% reduction in migration time, and 10-20% reduction in required migration buffer size.

Bio

Yashar Ganjali is a professor of computer science at the University of Toronto. He is a member of Computer Systems and Networks Group. He received his BSc in Computer Engineering from Sharif University of Technology, and his MSc in Computer Science from University of Waterloo. He completed his PhD in Electrical Engineering at Stanford University. His PhD dissertation studied the buffer sizing problem in Internet core routers, and showed the possibility of reducing buffer sizes from millions of packets to just a few packets in Internet core routers.

Dr. Ganjali’s research interests include packet switching architectures/algorithms, software-defined networking, data center networking, congestion control, network measurements, and online social networks. He has received several awards for his research including best paper award in Internet Measurement Conference 2008, best paper runner up in IEEE INFOCOM 2003 , best demo runner up in SIGCOMM 2008 , first and second prizes in NetFPGA Design Competition 2010, Cisco Research Award, and a Distinguished Faculty Award from Facebook.