Efficient Hierarchical Traffic Measurement in Software-Defined Datacenter Networks

Software-defined datacenters combine centralized resource management, software-defined networking, and virtualized infrastructure to meet diverse requirements of cloud computing. To fully realizing their capability in traffic engineering and flow-based bandwidth management, it is critical for the switches to measure network traffic for both individual flows between virtual machines and aggregate flows between clusters of physical or virtual machines. This paper proposes a novel hierarchical traffic measurement scheme for software-defined datacenter networks. It measures both aggregate flows and individual flows that are organized in a hierarchy with an arbitrary number of levels. The measurement is performed based on a new concept of hierarchical virtual counter arrays, which record each packet only once by updating a single counter, yet the sizes of all flows that the packet belongs to will be properly updated. We demonstrate that the new measurement scheme not only supports hierarchical traffic measurement with accuracy, but does so with memory efficiency, using a fewer number of counters than the number of flows.