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# DDDeviceProtocolString

String values for the manner in which an app interacts with a device.

```
struct DDDeviceProtocolString
```

## Discussion

When an app creates a device discovery extension to stream content to a third-party media receiver, the protocol is Discovery and Launch (DIAL), as designated by the [`DDDevice.Protocol.dial`](/documentation/DeviceDiscoveryExtension/DDDevice/Protocol-swift.enum/dial) option.

## Topics

### Creating a device protocol string

[`init(rawValue: String)`](/documentation/DeviceDiscoveryExtension/DDDeviceProtocolString/init(rawValue:))

Creates a string for the manner in which an app interacts with a device.

### Specifying a device protocol string

[`static let dial: DDDeviceProtocolString`](/documentation/DeviceDiscoveryExtension/DDDeviceProtocolString/dial)

A human-readable string for the Discovery and Launch protocol.

[`static let invalid: DDDeviceProtocolString`](/documentation/DeviceDiscoveryExtension/DDDeviceProtocolString/invalid)

A human-readable string for the default device protocol.

## Relationships

### Conforms To

[`Sendable`](/documentation/Swift/Sendable)

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

---

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