Domain Survey Definitions
These are definitions of terms used by the Internet Domain Survey.
Not everyone uses these terms with the same meanings.
- domain name
- A domain name is any name representing any record that exists
within the Domain Name System. ie. com, nw.com, www.nw.com
- domain
- A domain is a domain name that has name server (NS) records
associated with it. In other words, there may be subdomains or
hosts under it. ie. com, nw.com
- domain server
- A domain server is a system that hold all the records
associated with a particular domain, and answers queries about
those names.
- domains queried/domains missed
- Domains queried refers to how many domains we could query
by connecting to the domain server and asking it for a dump of
the domain. Domains missed is the number of domains that we
could not query, because we couldn't connect to the appropriate
server or the server refused the query.
- domain (top-level)
- A top-level domain name is either an ISO country code or one of
the generic domains (com/org/net/etc). It should be noted that there
is not necessarily any correlation between a country code and where
a host is actually located.
- duplicate host
- A single host name that maps to multiple IP addresses. When a host
like this is found in the survey, it is only counted once.
- host
- A host is a domain name that has an IP address (A) record
associated with it. This would be any computer system connected
to the Internet (via full or part-time, direct or dialup connections).
ie. nw.com, www.nw.com
- host name (or firstname)
- A host name is the first part (before the first dot)
of a hosts' domain name. ie. www
- network numbers (class a/b/c)
- A network number is the first part of an IP address that
identifies what network the hosts numbered in the rest of the address
are connected to. The Class A/B/C system is no longer used and the
data is presented only for historical reasons. It is no longer
possible to tell how many network numbers are in use by looking at IP
addresses, since the netmask can not be determined from the number.
Also, note that domains do not map directly to particular network
numbers and no correlation between them can be inferred.
- zone transfer
- A zone transfer is the process of downloading all the
records associated with part of a domain from a domain
server.
Internet Domain Survey