DCE: Test the real code of your protocols and applications over simulated networks

We present the Direct Code Execution (DCE) environment for ns-3, notable for being the first free open source framework for integrating Linux kernel and application code within a leading discrete-event network simulator. This new approach has many potential advantages over virtual-machine-based frameworks in terms of realism, reproducibility, avoidance of realtime execution constraints, configuration management, and the ability to debug a network-wide experiment from a single address space using common debugging tools. We provide an overview of DCE and illustrate some key features of this framework with two use cases, one involving thttpd, an HTTP server implementation, and another one involving the udp-perf traffic generator.