2.3. Delegation
Remember that one of the main goals of the design of the Domain Name
System was to decentralize administration? This is achieved through
delegation.
Delegating domains is a lot like delegating tasks at work. A manager
may break up a large project into smaller tasks and delegate
responsibility for each of these tasks to different employees.
Likewise, an organization administering a domain can divide it into
subdomains. Each of those subdomains can be
delegated to other organizations. This means
that an organization becomes responsible for maintaining all the data
in that subdomain. It can freely change the data, and even divide up
its subdomain into more subdomains and delegate those. The
parent domain
retains only pointers to sources of the subdomain's data so
that it can refer queriers there. The domain
stanford.edu, for example, is delegated to the
folks at Stanford who run the university's networks, as shown
in Figure 2-7.
Figure 2-7. stanford.edu is delegated to Stanford University
Not all organizations delegate away their whole domain, just as not
all managers delegate all their work. A domain may have several
delegated subdomains and also contain hosts that don't belong
in the subdomains. For example, the Acme Corporation (which supplies
a certain coyote with most of his gadgets) has a division in Rockaway
and its headquarters in Kalamazoo, so it might have a
rockaway.acme.com subdomain and a
kalamazoo.acme.com subdomain. However, the few
hosts in the Acme sales offices scattered throughout the U.S. would
fit better under
acme.com than under either
subdomain.
We'll explain how to create and delegate subdomains later. For
now, it's only important to understand that the term
delegation refers to assigning responsibility
for a subdomain to another organization.
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2.2. The Internet Domain Name Space | | 2.4. Name Servers and Zones |