For more information on drivers and available options, see [Network drivers](/manuals/engine/network/drivers/_index.md).

### `driver_opts`

`driver_opts` specifies a list of options as key-value pairs to pass to the driver. These options are
driver-dependent.

```yml
networks:
  frontend:
    driver: bridge
    driver_opts:
      com.docker.network.bridge.host_binding_ipv4: "127.0.0.1"
```

Consult the [network drivers documentation](/manuals/engine/network/_index.md) for more information.

### `attachable`

If `attachable` is set to `true`, then standalone containers should be able to attach to this network, in addition to services.
If a standalone container attaches to the network, it can communicate with services and other standalone containers
that are also attached to the network.

```yml
networks:
  mynet1:
    driver: overlay
    attachable: true
```

### `enable_ipv4`

{{< summary-bar feature_name="Compose enable ipv4" >}}

`enable_ipv4` can be used to disable IPv4 address assignment.

```yml
  networks:
    ip6net:
      enable_ipv4: false
      enable_ipv6: true
```

### `enable_ipv6`

`enable_ipv6` enables IPv6 address assignment.

```yml
  networks:
    ip6net:
      enable_ipv6: true
```

### `external`

If set to `true`:
 - `external` specifies that this network’s lifecycle is maintained outside of that of the application.
Compose doesn't attempt to create these networks, and returns an error if one doesn't exist.
 - All other attributes apart from name are irrelevant. If Compose detects any other attribute, it rejects the Compose file as invalid.

In the following example, `proxy` is the gateway to the outside world. Instead of attempting to create a network, Compose
queries the platform for an existing network simply called `outside` and connects the
`proxy` service's containers to it.

```yml
services:
  proxy:
    image: example/proxy
    networks:
      - outside
      - default
  app:
    image: example/app
    networks:
      - default

networks:
  outside:
    external: true
```

### `ipam`

`ipam` specifies a custom IPAM configuration. This is an object with several properties, each of which is optional:

- `driver`: Custom IPAM driver, instead of the default.
- `config`: A list with zero or more configuration elements, each containing a: