The controller placement problem

  • Authors:
  • Brandon Heller;Rob Sherwood;Nick McKeown

  • Affiliations:
  • Stanford University, Stanford, CA, USA;Big Switch Networks, Palo Alto, CA, USA;Stanford University, Stanford, CA, USA

  • Venue:
  • ACM SIGCOMM Computer Communication Review - Special october issue SIGCOMM '12
  • Year:
  • 2012

Quantified Score

Hi-index 0.00

Visualization

Abstract

Network architectures such as Software-Defined Networks (SDNs) move the control logic off packet processing devices and onto external controllers. These network architectures with decoupled control planes open many unanswered questions regarding reliability, scalability, and performance when compared to more traditional purely distributed systems. This paper opens the investigation by focusing on two specific questions: given a topology, how many controllers are needed, and where should they go? To answer these questions, we examine fundamental limits to control plane propagation latency on an upcoming Internet2 production deployment, then expand our scope to over 100 publicly available WAN topologies. As expected, the answers depend on the topology. More surprisingly, one controller location is often sufficient to meet existing reaction-time requirements (though certainly not fault tolerance requirements).