On 9/24/13 3:26 PM, Ming-Chen Zhao wrote:
From these old research papers, I can see the flow setup rate they can achieve is about 200-300 flows/sec. The bottleneck is the bandwidth between controller and openflow switches.
We saw more like 1,000 flows/s on the G8264, so things have improved a little.
However, there are no reports from industrial to discuss what the real flow setup rate they need... Can 200-300 flows/sec be enough to support a small datacenter network?
One way to begin to answer this question might be to consider STP or OSPF convergence time and compare it against OpenFlow. In some cases RSTP can converge in less than one second, but OpenFlow convergence time is proportional to the number of flows; at L2 the number of flows is at least the number of hosts. So an L2 OpenFlow network will converge slower than RSTP if it has a significant number of hosts. In an L3 network the number of flows might be equal to the number of subnets, so a small number of updates per second might be acceptable.
-- Wes Felter IBM Research - Austin _______________________________________________ openflow-discuss mailing list openflow-discuss@lists.stanford.edu https://mailman.stanford.edu/mailman/listinfo/openflow-discuss
