If you are referring to "Hosts do not identify themselve as domains!"
then forget about it: that statement is false.
I've reread rfc1035 and have to admit that it does say that hosts can be
domains. But it also does seem to specify use of the domain as what I'd
call FQDN, i.e. for example:
<domain-name> is a domain name represented as a series of labels, and
terminated by a label with zero length.
Where as host can be a single name with no "."
BTW - here are original definitions from rfc819 which appears to be the
one that started the use of "domain", I take it the use of "name" here is
somewhat synonymous with what I call a "host" and this definition of
domain is consistant with what I understood it as well:
address
An address is a numerical identifier for the topological location
of the named entity.
name
A name is an alphanumeric identifier associated with the named
entity. For unique identification, a name needs to be unique in
the context in which the name is used. A name can be mapped to an
address.
complete (fully qualified) name
A complete name is a concatenation of simple names representing
the hierarchical relation of the named with respect to the naming
universe, that is it is the concatenation of the simple names of
the domain structure tree nodes starting with its own name and
ending with the top level node name. It is a unique name in the
naming universe.
partially qualified name
A partially qualified name is an abbreviation of the complete name
omitting simple names of the common ancestors of the communicating
parties.
simple name
A simple name is an alphanumeric identifier unique only within its
parent domain.
domain
A domain defines a region of jurisdiction for name assignment and
of responsibility for name-to-address translation.
naming universe
Naming universe is the ancestor of all network entities.
naming environment
A networking environment employing a specific naming convention.
name service
Name service is a network service for name-to-address mapping.
name server
A name server is a network mechanism (e.g., a process) realizing
the function of name service.
naming authority
Naming authority is an administrative entity having the authority
for assigning simple names and responsibility for resolving naming
conflict.
parallel relations
A network entity may have one or more hierarchical relations with
respect to the naming universe. Such multiple relations are
parallel relations to each other.
multiple parentage
A network entity has multiple parentage when it is assigned a
simple name by more than one naming domain
--
William Leibzon
Elan Networks
william(_at_)elan(_dot_)net