---
title: subprotocol
framework: network
role: symbol
role_heading: Instance Property
path: network/nwprotocolwebsocket/response/subprotocol
---

# subprotocol

The selected subprotocol in a WebSocket server response.

## Declaration

```swift
let subprotocol: String?
```

## See Also

### Sending Handshake Responses

- [init(status:subprotocol:additionalHeaders:)](network/nwprotocolwebsocket/response/init(status:subprotocol:additionalheaders:).md)
- [NWProtocolWebSocket.Response.Status](network/nwprotocolwebsocket/response/status-swift.enum.md)
- [status](network/nwprotocolwebsocket/response/status-swift.property.md)
- [additionalHeaders](network/nwprotocolwebsocket/response/additionalheaders.md)