OpenFlow Protocol

Advanced Networking
OpenFlowOVSWiresharkPOX

Objective

Hands-on practice with openflow protocol in a network lab environment.

Tools & Technologies

  • OpenFlow
  • OVS
  • Wireshark
  • POX

Key Commands

ovs-ofctl add-flow br0 'priority=100,ip,actions=output:2'
ovs-ofctl del-flows br0
ovs-ofctl dump-ports br0

Lab Steps

01
OpenFlow Messages

Understand PACKET_IN, PACKET_OUT, FLOW_MOD, and STATS messages.

02
Flow Installation

Manually install flow entries using ovs-ofctl and observe traffic behavior.

03
Flow Timeouts

Configure hard_timeout and idle_timeout on flows.

04
Capture OpenFlow

Capture OpenFlow messages between switch and controller in Wireshark.

Challenges Encountered

  • Flow priority determines match order
  • Table-miss entries must be configured or packets are dropped

Key Takeaways

  • OpenFlow gives precise control over forwarding decisions
  • Pipeline processing allows complex match-action chains