Container NATs and Session-Oriented Standards: Friends or Foe?

This article highlights issues that arise when deploying network address translation middle-boxes through containers. We focus on Docker as the container technology of choice and present a thorough analysis of its networking model, with special attention to the default bridge network driver that is used to implement network address translation functionality. We discuss some unexpected shortcomings we identified and elaborate on the suitability of containers for deploying services based on the Interactive Connectivity Establishment standard protocol. To support our findings, we present experiments we conducted in a real-world operational environment, namely a WebRTC service based on the Janus media server.