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AS112 FAQ (in Bulgarian)
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Because most answers generated by the Internet's root name server system are negative, and many of those negative answers are in response to PTR queries for RFC1918 and other ambiguous addresses, as follows: There are now separate (non-root) servers for these queries, described below.

IPv4 Anycast

As a way to distribute the load for RFC1918-related queries, we use IPv4 anycast addressing. The address block is and its origin AS is 112. This address block is advertised from multiple points around the Internet, and these distributed servers coordinate their responses and back end statistical analyses.

RFC1918 Server Operators

Each such server also has a well known unicast address for diagnostic purposes:

Well known addresses

The well known addresses for authoritative name service for zones associated with RFC1918 PTR queries are:
listed in SOA RR, receives mostly updates
listed in NS RR, receives mostly queries
listed in NS RR, receives mostly queries

Client side operations

To find out which actual server is responding to your anycast queries, use the UNIX dig command, as in:
	dig any
The response should look something like this:
	@ 15S	TXT	"Internet Software Consortium, Inc." "Palo Alto, CA, USA"
		TXT	"See for more information."
		SOA (
			2002050100	; serial
			1H		; refresh
			10M		; retry
			4w2d		; expiry
			15S )		; minimum
Where the SOA RR MNAME tells the host name of the answering anycast server, the SOA RR ANAME tells the e-mail address of the server's administrator, and some unordered TXT RR's tell other information which may be of interest. (Note: the whole response must fit in a 512 octet DNS/UDP datagram.)


To arrange to host anycast service for these zones, contact the AS112 Project. You should know how to configure both intra-AS routing, and inter-AS routing using BGP, and you should plan on running a stealth slave of the IANA.ORG zone so that your servers will return appropriate glue in their responses.
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