Dockemu: An IoT Simulation Framework Based on Linux Containers and the ns-3 Network Simulator — Application to CoAP IoT Scenarios

Large-scale and realistic simulations have been a pending issue in IoT research and development, hampering the design and optimization of networked systems. This paper presents new features added to the Dockemu open-source project, aimed at making it a valuable framework for such studies. The framework is based on the use of Linux Docker containers for the individual constrained nodes, and the ns-3 network simulator to emulate the network and connect the nodes during the simulation. Both technologies combined enable the capacity to simulate a huge number of lightweight nodes under realistic network conditions. The Linux interface mechanism used to interconnect the containers and the ns-3 simulation are described in detail. We also explain how LTE and LR-WPAN network technologies were added to the framework in order to cover a wide range of scenarios. Details on how Ansible has been used to orchestrate the setup and execution of the testing framework are given, too, showing how this widely-used devops tool can replace different programming and scripting languages for the orchestration of a simulation framework. Finally, the paper includes an example of IoT scenario simulation, using a real implementation of the CoAP protocol and involving a relevant number of nodes.