Network configuration reference
The top-level networks key lets you specify networks to be created.
For a full explanation of Compose’s use of Docker networking features and all network driver options, see the Networking guide.
For Docker Labs tutorials on networking, start with Designing Scalable, Portable Docker Container Networks
Specify which driver should be used for this network.
The default driver depends on how the Docker Engine you’re using is configured, but in most instances it is bridge on a single host and overlay on a Swarm.
The Docker Engine returns an error if the driver is not available.