rfc1480.txt
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<org-name>.GEN.<state-code>.US.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
VIEW OF SECOND LEVEL DOMAINS UNDER US
+-------+
| US |
+-------+
|
+----------------------------------+
| | | | |
+-----+ +-----+ +-----+ +-----+ +-----+
| FED | | DNI | | TX | | SD | | CA |
+-----+ +-----+ +-----+ +-----+ +-----+
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Cooper & Postel [Page 6]
RFC 1480 The US Domain June 1993
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
SCHOOL AND LIBRARY VIEW
+-----+
| CA |
+-----+
|
+------------------------------------------------+
| | | | |
+-----+ +-----+ +-----+ +-------------+ +-----+
| K12 | | CC | | TEC | | LOS ANGELES | | LIB |
+-----+ +-----+ +-----+ +-------------+ +-----+
/ \ /|\ /|\ /|\ /|\
+--------+ +---+ +---+ +--------+ +----------+ +------+
|sch dist| |PVT| |SJC| |WM TRADE| |pvt school| |MALIBU|
+--------+ +---+ +---+ +--------+ +----------+ +------+
/|\ /|\
+--------+ +--------+
|sch name| |sch name|
+--------+ +--------+
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
VIEW OF STATE, REGIONAL, and GENERAL AGENCIES
+-----+
| CA |
+-----+
|
+-------------------------+
| | |
+-------+ +--------+ +-----+
| STATE | |DISTRICT| | GEN |
+-------+ +--------+ +-----+
/|\ /|\ /|\
+--------+ +------+ +---------+
|CALTRANS| |SCAQMD| |domain pk|
---------+ +------+ +---------+
|
+--------+
|TCEW100E|
+--------+
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Cooper & Postel [Page 7]
RFC 1480 The US Domain June 1993
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
VIEW OF LOCALITY
+-----+
| CA |
+-----+
|
+-----------------------------------+
| |
+-------------------------+ +----------------+
| LOS ANGELES | | SANTA MONICA |
+-------------------------+ +----------------+
/ | | /|\ | /|\
/ | | | | |
+---+ +--+ +--+ +-----------+ +--+ +---+
|bus| |CI| |CO| | pvt school| |CI| |bus|
+---+ +--+ +--+ +-----------+ +--+ +---+
/\ | |
/ \ | +------------+
/ \ | |HARBOR GUARD|
/ \ | +------------+
+-----+ +-----+ +-----+ +----+
|FIRE | |ADMIN| |PARKS| |FIRE|
+-----+ +-----+ +-----+ +----+
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
2.1 State Codes
The state codes are the two letter US Postal abbreviations. For
example: "CA" California.
2.2 Locality Names
Within the state name space there are "locality" names, some may be
cities, some may be counties, some may be local names, but not
incorporated entities.
Registered names under "locality" could be like:
<hostname>.CI.<locality>.<state>.US ==> city gov't agency
<hostname>.CO.<locality>.<state>.US, ==> county gov't agency
<hostname>.<locality>.<state>.US ==> businesses
In the cases where the locality name is a county, there is a branch
under the locality name, called "county" or "CO", that is used by the
county government. Businesses are registered directly under the
locality name.
Cooper & Postel [Page 8]
RFC 1480 The US Domain June 1993
Under the city locality name space there is a "city" or "CI" branch
for city government agencies. As usual, businesses and private
schools may register directly under the city name.
In the case where there is both a county and a city with the same
locality name there is no problem, since the names will be unique
with the "CO" or "CI" keyword. In our area the county has a fire
department and the city has its own fire department. They could have
names like:
Fire-Dept.CI.Los-Angeles.CA.US
Fire-Dept.CO.Los-Angeles.CA.US
Cities may be named (designated) by their full name (spelled out with
hyphens replacing spaces (e.g., Los-Angeles or Fort-Collins), or by a
city code. The first choice is the full city name. In some cases it
may be appropriate to use the well-known city abbreviation known
throughout a locality. However, it is very desirable that all users
in the same city use the same designator for the city. That is, any
particular locality should have just one DNS name.
Some users would like names associated with a greater metropolitan
area or region like the "Bay Area" or "Tri-Cities". One problem with
this is that these names are not necessarily unique within a state.
The best thing to do in this case is to use the larger metropolitan
city in your hostname. Cities and counties are used.
Should all the names be obvious? Trying to do this is desirable and
also impossible. There will come a point when the obviously right
name for an organization is already taken. As the system grows this
will happen with increasing frequency. While ease of use to the end
user is desirable, a higher priority must be placed on having a
system that operates. This means that the manageability of the
system must have high consideration.
The reason the DNS was created was to subdivide the problem of
maintaining a list of hosts in the Internet into manageable portions.
The happy result is that this subdivision makes name uniqueness
easier and promotes logical grouping. What is a "logical grouping"
though, always depends on the viewer.
Many levels of delegation are needed to keep the zone files
manageable. Many sections of the name space are needed to allow
unique names to be easily added.
Cooper & Postel [Page 9]
RFC 1480 The US Domain June 1993
Way back in the olden days, when the Internet was invented, some
thought that an 8-bit network number would be more than enough to
number all the networks that would ever exist. Today, there are over
10,000 networks operating in the Internet, and arguments are made
about the doubling time being 2 years versus 4 years.
One concern is that things will continue to grow dramatically, and
this will require more subdivision of the domain name management.
Maybe the plan for the US Domain is overkill on growth planning, but
there has never been overplanning for growth yet.
When things are bigger, names have to be longer. There is an
argument that with only 8-character names, and in each position allow
a-z, 0-9, and -, you get 37**8 = 3,512,479,453,921 or 3.5 trillion
possible names. It is a great argument, but how many of us want
names like "xs4gp-7q". It is like license plate numbers, sure some
people get the name they want on a vanity plate, but a lot more
people who want something specific on a vanity plate can't get it
because someone else got it first. Structure and longer names also
let more people get their "obviously right" name.
2.3 Schools
K12 schools are connecting to the Internet and registering in the
Internet DNS. A decision has been made by the IANA (after
consultation with the new InterNIC Internet Registry and the Federal
Networking Council (FNC)) to direct these school registrations to the
US domain using the naming structure described here.
There is a need for competent, experienced, volunteers to come
forward to act as third and perhaps fourth level registries and to
operate delegated portions of the DNS.
There are two reasons for registering schools in the US Domain. (1)
uniqueness of names, and (2) management of the database.
1. Name Uniqueness:
There are many "Washington" high schools, only one can be
"Washington.EDU" (actually none can be, since that name is used
by a University. There will be many name conflicts if all
schools attempt to register directly under EDU.
In addition, in some districts, the same school name is used at
different levels, for example, Washington Elementary School and
Washington High School. We suggest that when necessary, the
keywords "Elementary", "Middle", and "High" be used to
distinguish these schools. These keywords would only be used
Cooper & Postel [Page 10]
RFC 1480 The US Domain June 1993
when they are needed, if the school's name is unique without
such keywords, don't use them.
2. Database Management:
One goal of the DNS is to divide up the management of the name
database in to small pieces. Each piece (or "zone" in DNS
terminology) could be managed by a distinct administrator.
Adding all the high schools to the EDU domain will make the
already large zone file for EDU even larger, possibly to the
point of being unmanageable.
For both these reasons it is necessary to introduce structure into
names. Structure provides a basis for making common names unique in
context, and for dividing the management responsibility.
The US Domain has a framework established and has registered many
schools already in this structured scheme. The general form is:
<school>.<district>.K12.<state>.US.
For example: Hamilton.LA-Unified.K12.CA.US
Public schools are usually organized by districts which can be larger
or smaller than a city or county. For example, the Portland school
district in Oregon, is in three or four counties. Each of those
counties also has non-Portland districts.
It makes sense to name schools within districts. However districts
often have the same name as a city or county so there has to be a way
to distinguish a public school district name from some other type of
locality name. The keyword "K12" is used for this.
For example, typical K12 school names currently used are:
IVY.PRS.K12.NJ.US
DMHS.JCPS.K12.KY.US
OHS.EUNION.K12.CA.US
BOHS.BREA.K12.CA.US
These names are generally longer than the old alternative of shorter
names in the EDU domain, but that would not have lasted long without
a significant number of schools finding that their "obviously
correct" name has already been used by some other school.
Cooper & Postel [Page 11]
RFC 1480 The US Domain June 1993
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