AS112

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The AS112 project is a group of volunteer-administered name server operators, who run an anycast instance of name servers that answer for the RFC 1918 reverse DNS networks, and the reverse address space of link-local RFC 3330 and RFC 3927 networks.

10.0.0.0/8
169.254.0.0/16
172.16.0.0/12
192.168.0.0/16

All of the AS112 nodes were originally run by a few of the Root nameserver operators, but later the group of volunteers has grown to include many other organizations.

[edit] Background

Before 2001, the in-addr.arpa zones for the RFC 1918 networks were delegated to a single instance of name servers, blackhole-1.iana.org and blackhole-2.iana.org. The IANA-run servers were under increasing load from improperly-configured NAT networks, leaking out reverse DNS queries, which eventually caused unnecessary load on the root servers. The decision was made by a small subset of root server operators to run the reverse delegations using a model as described in RFC 3258; each announcing the network using the autonomous system number of 112.

[edit] Specific Configuration

The name servers participating in the AS112 project are each configured to answer authoritatively for the following zones:

For the 10.0.0.0/8 network:
- 10.in-addr.arpa
For the 169.254.0.0/16 network (RFC 3927)
- 254.169.in-addr.arpa
For the 172.16.0.0/12 network:
- 16.172.in-addr.arpa
- 17.172.in-addr.arpa
- 18.172.in-addr.arpa
- 19.172.in-addr.arpa
- 20.172.in-addr.arpa
- 21.172.in-addr.arpa
- 22.172.in-addr.arpa
- 23.172.in-addr.arpa
- 24.172.in-addr.arpa
- 25.172.in-addr.arpa
- 25.172.in-addr.arpa
- 26.172.in-addr.arpa
- 27.172.in-addr.arpa
- 28.172.in-addr.arpa
- 29.172.in-addr.arpa
- 30.172.in-addr.arpa
- 31.172.in-addr.arpa
For the 192.168.0.0/16 network:
- 168.192.in-addr.arpa
For unique identification purposes:
- hostname.as112.net