CORE: A real-time network emulator

We present CORE (common open research emulator), a real-time network emulator that allows rapid instantiation of hybrid topologies composed of both real hardware and virtual network nodes. CORE uses FreeBSD network stack virtualization to extend physical networks for planning, testing and development, without the need for expensive hardware deployments. We evaluate CORE in wired and wireless settings, and compare performance results with those obtained on physical network deployments. We show that CORE scales to network topologies consisting of over a hundred virtual nodes emulated on a typical server computer, sending and receiving traffic totaling over 300,000 packets per second. We demonstrate the practical usability of CORE in a hybrid wired-wireless scenario composed of both physical and emulated nodes, carrying live audio and video streams.