Once you've decided how many subdomains you'd like to create and what
they correspond to, you should choose good names for them. Rather than
unilaterally deciding on your subdomains' names, it's considered
polite to involve your future subdomain administrators and their
constituencies in the decision. In fact, you can leave the decision
entirely to them, if you like.
This can lead to problems, though. It's nice to use a relatively
consistent naming scheme across your subdomains. It makes it easier
for users in one subdomain, or outside your domain entirely, to guess
or remember your subdomain names, and to figure out in which domain a
particular host or user lives.
Leaving the decision to the locals can result in naming
chaos. Some will want to use geographical names, others will insist on
organizational names. Some will want to abbreviate, others will want
to use full names.
Therefore, it's often best to establish a naming convention
before choosing subdomain names. Here are some suggestions from our
In a dynamic company, the names of organizations can change
frequently. Naming subdomains organizationally in a climate like this
can be disastrous. One month the Relatively Advanced Technology
) group seems stable enough, the next month
they've been merged into the Questionable Computer Systems
organization, and the following quarter they're all sold to a German
conglomerate. Meanwhile, you're stuck with well-known hosts in a
subdomain whose name no longer has any meaning.
Geographical names are more stable than organizational names,
but sometimes not as well known. You may know that your famous
Software Evangelism Business Unit is in Poughkeepsie or Waukegan, but
people outside your company may have no idea where it is (and might
have trouble spelling either name).
Don't sacrifice readability for convenience. Two-letter
subdomain names may be easy to type, but impossible to recognize. Why
and have it
confused with your Information Technology organization, when for a
paltry three more letters you can use the full name and eliminate any
Too many companies use cryptic, inconvenient domain names. The
general rule seems to be: the larger the company, the more
indecipherable the domain names. Buck the trend: make the names of
your subdomains obvious!
Don't use existing or reserved
top-level domain names as subdomain names. It might seem sensible to
use two-letter country abbreviations for your international
subdomains, or to use organizational top-level domain names like
for your networking
organization, but it can cause nasty problems. For example, naming
your Communications department's subdomain
might impede your ability to
communicate with hosts under the top-level
domain. Imagine the administrators
their new Sun workstation
and their new
(they aren't the most imaginative
folks): users anywhere within your domain sending mail to friends at
could have their letters end up in
subdomain, since the name of your parent zone may be in some of your
hosts' search lists.