Docker utilizes Linux kernel mechanisms to manage container networking through network namespaces. These namespaces provide isolated network stacks, including unique interfaces, routing tables, and firewall rules, preventing conflicts between processes.
The platform employs virtual network components to facilitate communication. Virtual Ethernet (veth) pairs act as cables connecting isolated environments, while bridges function as virtual switches, linking multiple containers into a unified network.
Docker supports several networking modes. The default bridge mode uses a virtual switch and NAT for connectivity. Host mode shares the host's network stack directly, while macvlan and ipvlan allow containers to appear as individual devices on the physical network.
For multi-host environments, the overlay mode creates a distributed network using tunnels like VXLAN. Additionally, Docker automates NAT via netfilter rules, enabling containers to access external networks and expose services without manual configuration.
