- · Decoupled Data and Control plane
- Can Evolve Independently
- · Can have different Network Topologies
- · Can use Different Technologies
Why SDN ?
One Possible SDN Design: Push all the control functionality to a Centralized Controller
How we can overcome?
- Level Parallelism in multicore systems
- Improve I/O performance
- Reduce the number of requests forwarded to controller: Short lived packets will be handled in the data path. Only larger flows are forwarded to the controller.
Another possible SDN Design: Distribute state and/or Computation of the Control Functionality over Multiple Controllers
Steps of Flow setup process
Steps involved in Converging on a link Failure
Resiliency to failures and convergence time are key concerns
in Network Performance. If we use a single controller, resiliency to failures
will be a major issue. We can use multi-controller networks with appropriate
controller discovery mechanisms.
SDN @ Different Network settings
Reference: On Scalability of Software-Defined Networking Paper published by Soheil Hassas, Yeganeh, Amin Tootoonchian and Yashar Ganjali University of Toronto.