---
title: protocolType
framework: mediadevice
role: symbol
role_heading: Instance Property
path: mediadevice/mediadeviceextension/protocoltype
---

# protocolType

The communication protocol that this extension implements.

## Declaration

```swift
@MainActor var protocolType: UTType { get }
```

## Mentioned in

Creating a media device extension

## Declaring the Protocol Type

Declaring the Protocol Type Declare a custom Uniform Type Identifier in your extension’s Info.plist using UTExportedTypeDeclarations. The type must conform to public.media-sharing-protocol: <key>UTExportedTypeDeclarations</key> <array>     <dict>         <key>UTTypeIdentifier</key>         <string>com.example.sharingprotocol</string>         <key>UTTypeDescription</key>         <string>My Sharing Protocol</string>         <key>UTTypeConformsTo</key>         <array>             <string>public.media-sharing-protocol</string>         </array>         <key>UTTypeIcons</key> 		<dict> 			<key>UTTypeSymbolName</key> 			<string>sharingprotocol.logo</string> 		</dict>     </dict> </array> UTTypeIdentifier: A reverse-DNS string that uniquely identifies your protocol. Media apps receive this value through AVSystemRoute/protocolType and use it to determine which protocol is active. UTTypeDescription: A human-readable name for the protocol. The system may display this in user interfaces such as the route picker. UTTypeConformsTo: Must include public.media-sharing-protocol. Returning the Type Return a UTType whose identifier matches the UTTypeIdentifier declared in Info.plist: var protocolType: UTType {     UTType("com.example.sharingprotocol")! }