instruction: Create a comprehensive Dockerfile for networking applications with best practices
output: ```dockerfile
  from containers that aren't connected to that bridge network. The
  Docker bridge driver automatically installs rules in the host machine so that
  containers on different bridge networks can't communicate directly with each
  other.Bridge networks apply to containers running on the same Docker daemon host.
  For communication among containers running on different Docker daemon hosts, you
  can either manage routing at the OS level, or you can use an
  overlay network.When you start Docker, a default bridge network (also
  called bridge) is created automatically, and newly-started containers connect
  to it unless otherwise specified. You can also create user-defined custom bridge
  networks. User-defined bridge networks are superior to the default bridge
  network.Differences between user-defined bridges and the default bridgeUser-defined bridges provide automatic DNS resolution between containers.Containers on the default bridge network can only access each other by IP
  addresses, unless you use the --link option, which is
  considered legacy. On a user-defined bridge network, containers can resolve
  each other by name or alias.Imagine an application with a web front-end and a database back-end. If you call
  your containers web and db, the web container can connect to the db container
  at db, no matter which Docker host the application stack is running on.If you run the same application stack on the default bridge network, you need
  to manually create links between the containers (using the legacy --link
  flag). These links need to be created in both directions, so you can see this
  gets complex with more than two containers which need to communicate.
  Alternatively, you can manipulate the /etc/hosts files within the containers,
  but this creates problems that are difficult to debug.User-defined bridges provide better isolation.All containers without a --network specified, are attached to the default bridge network. This can be a risk, as unrelated stacks/services/containers are then able to communicate.Using a user-defined network provides a scoped network in which only containers attached to that network are able to communicate.Containers can be attached and detached
  ```