I've been reading this ICANN agreement on new TLDs and it has this section on DNS service availability, which i don't completely understand:
Refers to the ability of the group of listed-as-authoritative name servers of a particular domain name (e.g., a TLD), to answer DNS queries from DNS probes. For the service to be considered available at a particular moment, at least, two of the delegated name servers registered in the DNS must have successful results from “DNS tests” to each of their public-DNS registered “IP addresses” to which the name server resolves. If 51% or more of the DNS testing probes see the service as unavailable during a given time, the DNS service will be considered unavailable.
I'm not 100% sure of the part in bold: does "public" refer to the DNS or to the IP addesses? It looks like there's a mistake and that the hyphen should have been after "DNS". So basically does it mean "the public IP addresses registered in the DNS"?