DIAL is a netflix+youtube mod of SSDP, implemented by some TVs, by ChromeCast devices, and by future HbbTV-v2-compliant devices.
If you are already using Cling for UPnP and you need to discover DIAL devices, then you can reuse Cling for DIAL discovery with small modifications.
Because DIAL is somewhat of a hack, and not UPnP-compliant, DIAL devices end up as "failed remote device discoveries".
Cling has a way to listen for that, so my modifications are limited to parsing a DIAL-specific HTTP header and making its value available in the failed Remote Device object. The remainder of the DIAL protocol is a REST API, and thus out of scope.
Interested parties can see the mods in the fork https://github.com/COLTRAM/cling If there is interest, I can create a pull request, but given the non-UPnP-compliance of DIAL, I am not sure if it is welcome.