**A warm welcome to DNS** Note: this page is part of the '[hello-dns](https://powerdns.org/hello-dns/)' documentation effort. # Non-IETF DNS standards * RPZ: Response Policy Zone is a framework for blocking, dropping queries or spoofing responses based on domain names, response IP addresses or nameservers used during resolution. It has long lived as an [ISC Technical Note](https://ftp.isc.org/isc/dnsrpz/isc-tn-2010-1.txt), and failed to become an IETF standard. It is nevertheless very useful, and there is an industry of RPZ providers. Policies are described by zones and are typically transmitted over IXFR. * RRL: Response Rate Limiting * DNSCrypt * Curvedns