Internet-in-a-Box: emulating datacenter network architectures using FPGAs

In this paper we describe the Internet-in-a-Box datacenter network emulator, an FPGA-based tool for researchers to rapidly experiment with O(10,000) node datacenter network architectures. Our basic approach to emulation involves constructing a model of the target architecture by composing simplified hardware models of key datacenter building blocks, including switches, routers, links, and servers. Since models in our system are implemented in programmable hardware, designers have full control over emulated buffer sizes, line rates, topologies, and many other network properties. Full system control also gives researchers a significant degree of system visibility. Additionally, because our node model emulates servers using a full SPARC v8 ISA compatible processor, each node in the network is capable of running real applications. This allows researchers to study a network under complex real-world workloads at a scale that matches that of a large datacenter today. Moreover, because the system is a private testbed, experiments can be deterministic and therefore reproduced by other researchers. Lastly, the system is cost effective for designers, and we show that using FPGA technology on the market today we can actually emulate a network of 256-nodes for about $2,000.