MCSA/MCSE Self-Paced Training Kit (Exam 70-270): Installing ...

Domain-Naming Guidelines
Lesson 2 Understanding the Domain Name System
13-29
When you create a domain namespace, consider the following domain guidelines and
standard naming conventions:
■ Limit the number of domain levels. Typically, DNS host entries should be three or
four levels down the DNS hierarchy and no more than five levels down the hierarchy.
The numbers of levels increase the administrative tasks.
■ Use unique names. Each subdomain must have a unique name within its parent
domain to ensure that the name is unique throughout the DNS namespace.
■ Use simple names. Simple and precise domain names are easier for users to
remember. They also enable users to search intuitively and locate Web sites or
other computers on the Internet or an intranet.
■ Avoid lengthy domain names. Domain names can be up to 63 characters, including
periods. The total length of an FQDN cannot exceed 255 characters. Casesensitive
naming is not supported.
■ Use standard DNS characters and Unicode characters.
■ Windows 2000 Server and Windows Server 2003 support the following standard
DNS characters: a–z, 0–9, and the hyphen (-), as defined in RFC 1035.
■ The DNS Service also supports the Unicode character set. The Unicode character
set includes additional characters not found in the American Standard Code for
Information Interchange (ASCII) character set; these additional characters are
required for languages such as French, German, and Spanish.
Note Use Unicode characters only if all servers running the DNS Service in your environment
support Unicode. For more information about the Unicode character set, read RFC 2044
by searching for “RFC 2044” with your Web browser.
What Are Zones?
A zone represents a discrete portion of the domain namespace. Zones provide a way
to partition the domain namespace into manageable sections, and they provide the following
functions:
■ Multiple zones in a domain namespace are used to distribute administrative tasks
to different groups. For example, Figure 13-9 depicts the microsoft.com domain
namespace divided into two zones. These zones allow one administrator to manage
the microsoft and sales domains, and another administrator to manage the
development domain.