The philosophy of SDN has introduced new challenges in network system management. In contrast to traditional network devices that contained both the control and the data plane functionality in a tightly coupled manner, SDN technologies separate the two network planes, and define a remote API for low-level device configuration. Nonetheless, the enhanced flexibility of the SDN paradigm is prone to create novel performance and scalability bottlenecks in the network.

To help network managers and application developers better understand the actual behavior of SDN implementations, we present a hardware/software co-design that enables switch characterization at 40Gbps and beyond. We conduct an evaluation of both software and hardware switches. We expose the unwanted effects of the OpenFlow barrier primitive, potential misbehaviors when adding or modifying a batch of rules and how simple operations, such as packet modification, can impact the switch forwarding performance.
We release the code publicly as open source to promote experiments reproducibility, as well as encourage the network community to evolve our solution.