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Applying Dockemu to CoAP IOT Scenarios

Date: 2026-06-06

Link: https://link.springer.com/chapter/10.1007/978-3-030-35944-7_4

Motivation

The authors aimed to create a cost-effective, reproducible, and highly scalable hybrid testing environment that runs real production software on generic low-cost hardware. By upgrading the Dockemu framework to support complex cell and mesh topologies, they tried to find a way to seamlessly stress-test application protocols under realistic conditions.

Methodology

  • Individual constrained nodes run software clients or servers inside Linux Docker containers to use kernel namespace features to optimize RAM and scale up the number of simultaneous endpoints.
  • Uses ns-3 with the realtime scheduler to match with system time.
  • For each container, Dockemu creates a virtual peer interface connected to a Linux bridge and a Tap interface, which binds to an emulated node via the ns-3 Tap NetDevice module.
  • Network interfaces mapping into ns-3 act as "ghost nodes"; they do not generate traffic but instead use Inter-Process Communication (IPC) to pass packets from the Docker Containers into the ntework inside ns-3.
  • LTE Networks: Dockemu bridges containers to cellular nodes using the ns-3 LENA module by passing traffic through a high bandwidth and "near-zero latency" CSMA link.
  • LR-WPAN Mesh: Low-rate mesh networks are emulated using the lr-wpan and 6lowpan modules, routing traffic to a simulated 6LoWPAN adapter that handles standard 127-byte header compression and encapsulation.
  • All of this is executed with a completely rewritten framework that replaces all the Python and bash scripts into Ansible Playbooks for install, prepare, execute, and cleanup, using a single YAML file.

Drawbacks

  • The topology configuration only allows for 2 distinct nodes that are defined, client and server
  • There exists no cross-over configuration where multiple different network types are used to communicate.
  • It still requires to modify and write C++ classes inside ns3 to adjust the simulation logic.
  • The fake PAN association bypasses the initial handshake and configurations, so it doesn't mimic actual interactions.
  • The containers are setup very simple, there are no fine grained controls should someone need.