The zone is named dns-over-tls.verisignlabs.com and it has A, AAAA, and TXT records for names from 'L001' to 'L100'.
The IP address of the server is currently 126.96.36.199.
Server key file is available to download here: nsd.key
The zone is signed
|Server type||Hosted by||IP addresses||Server key||Hostname for TLS authentication|
starttls.verisignlabs.com [Note that this
is a self-signed certificate so does not pass
authentication by default.]