_raop._tcp
The raop._tcp service points to the backend RTSP server instance. And the fields below must be included in the published service.
| Field | Required | Description | Sample Value |
|---|---|---|---|
| am | required | The device model | "AppleTV3,2" |
| cn | required | The supported audio codecs | "0,1,2,3" |
| et | required | The supported encryption types | "0,3,5" |
| ft | required | The supported features | "0x527FFFF7" |
| pk | required | unknown | The same with _airplay._tcp service |
| tp | required | The transmission protocol "TCP" or "UDP" | |
| vs | required | The server software version | "220.68" |
| vv | required | unknown | The same with _airplay._tcp service |
| vn | required | unknown | "65537" |
| da | required | unknown | "true" |
| sf | required | unknown | "0x04" |
most of the fields are described in the AirTunes Service section.