VL2: A Scalable and Flexible Data Center Network

Overview

To be agile and cost effective, data centers should allow dynamic resource allocation across large server pools. In particular, the data center network should enable any server to be assigned to any service. To meet these goals, the paper presentsVL2, a practical network architecture that scales to support huge data centers with uniform high capacity between servers, performance isolation between services, and Ethernet layer-2 semantics. VL2 uses flat addressing to allow service instances to be placed anywhere in the network, Valiant Load Balancing to spread traffic uniformly across network paths, and end-system based address resolution to scale to large server pools, without introducing complexity to the network control plane.