rfc1480.txt

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Network Working Group                                          A. Cooper
Request for Comments: 1480                                     J. Postel
Obsoletes: 1386                                                June 1993

                             The US Domain


Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard.  Distribution of this memo is
   unlimited.

Table of Contents

   1.  Introduction ................................................  2
       1.1  The Internet Domain Name System.........................  2
       1.2  Top-Level Domains.......................................  3
       1.3  The US Domain ..........................................  4
   2.  Naming Structure ............................................  4
       2.1  State Codes ............................................  8
       2.2  Locality Names..........................................  8
       2.3  Schools ................................................ 10
       2.4  State Agencies.......................................... 15
       2.5  Federal Agencies ....................................... 15
       2.6  Distributed National Institutes......................... 15
       2.7  General Independent Entities............................ 16
       2.8  Examples of Names....................................... 17
   3.  Registration ................................................ 20
       3.1  Requirements ........................................... 20
       3.2  Direct Entries ......................................... 21
       3.2.1   IP-Hosts............................................. 21
       3.2.2   Non-IP Hosts ........................................ 21
       3.3  Delegated Subdomains ................................... 24
       3.3.1   Delegation Requirement............................... 26
       3.3.2   Delegation Procedures ............................... 28
       3.3.3   Subdomain Contacts................................... 29
   4.  Database Information......................................... 30
       4.1  Name Servers ........................................... 30
       4.2  Zone files ............................................. 30
       4.3  Resource Records ....................................... 31
       4.3.1   "A" Records ......................................... 32
       4.3.2   CNAME Records ....................................... 32
       4.3.3   MX Records .......................................... 33
       4.3.4   HINFO Records ....................................... 33
       4.3.5   PTR Records ......................................... 33
       4.4  Wildcards .............................................. 34
   5.  References .................................................. 35



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   6.  Security Considerations ..................................... 35
   7.  Authors' Addresses .......................................... 36
   Appendix-I:  US Domain Names BNF................................. 37
   Appendix-II: US Domain Questionnaire ............................ 42

1. INTRODUCTION

   1.1 The Internet Domain Name System

   The Domain Name System (DNS) provides for the translation between
   hostnames and addresses.  Within the Internet, this means translating
   from a name such as "venera.isi.edu", to an IP address such as
   "128.9.0.32".  The DNS is a set of protocols and databases.  The
   protocols define the syntax and semantics for a query language to ask
   questions about information located by DNS-style names.  The
   databases are distributed and replicated.  There is no dependence on
   a single central server, and each part of the database is provided in
   at least two servers.

   The assignment of the 32-bit IP addresses is a separate activity.  IP
   addresses are delegated by the central Internet Registry to regional
   authorities (such as the RIPE NCC for Europe) and the network
   providers.

   To have a network number assigned please contact your network service
   provider or regional registration authority.  To determine who this
   is (or as a last resort), you can contact the central Internet
   Registry at [e-mail].

   In addition to translating names to addresses for hosts that are on
   the Internet, the DNS provides for registering DNS-style names for
   other hosts reachable (via electronic mail) through gateways or mail
   relays.  The records for such name registrations point to an Internet
   host (one with an IP address) that acts as a mail forwarder for the
   registered host.  For example, the host "bah.rochester.ny.us" is
   registered in the DNS with a pointer to the mail relay
   "relay1.uu.net".  This type of pointer is called an MX record.

   This gives electronic mail users a uniform mail addressing syntax and
   avoids making users aware of the underlying network boundaries.

   The reason for the development of the domain system was growth in the
   Internet.  The hostname to address mappings were maintained by the
   InterNIC in a single file, called HOSTS.TXT, which was FTP'd by all
   the hosts on the Internet.  The network population was changing in
   character.  The time-share hosts that made up the original ARPANET
   were being replaced with local networks of workstations.  Local
   organizations were administering their own names and addresses, but



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   had to wait for the NIC to make changes in HOSTS.TXT to make the
   changes visible to the Internet at large.  Organizations also wanted
   some local structure on the name space.  The applications on the
   Internet were getting more sophisticated and creating a need for
   general purpose name service.  The idea of a hierarchical name space,
   with the hierarchy roughly corresponding to organizational structure,
   and names using "." as the character to mark the boundary between
   hierarchy levels was developed.  A design using a distributed
   database and generalized resources was implemented.

   The DNS provides standard formats for resource data, standard methods
   for querying the database, and standard methods for name servers to
   refresh local data from other name servers.

   1.2  Top-Level Domains

   The top-level domains in the DNS are EDU, COM, GOV, MIL, ORG, INT,
   and NET, and all the 2-letter country codes from the list of
   countries in ISO-3166.  The establishment of new top-level domains is
   managed by the Internet Assigned Numbers Authority (IANA).  The IANA
   may be contacted at [e-mail].

   Even though the original intention was that any educational
   institution anywhere in the world could be registered under the EDU
   domain, in practice, it has turned out with few exceptions, only
   those in the United States have registered under EDU, similarly with
   COM (for commercial). In other countries, everything is registered
   under the 2-letter country code, often with some subdivision.  For
   example, in Korea (KR) the second level names are AC for academic
   community, CO for commercial, GO for government, and RE for research.
   However, each country may go its own way about organizing its domain,
   and many have.

   There are no current plans of putting all of the organizational
   domains EDU, GOV, COM, etc., under US.  These name tokens are not
   used in the US Domain to avoid confusion.

   Currently, only four year colleges and universities are being
   registered in the EDU domain.  All other schools are being registered
   in the US Domain.

   There are also concerns about the size of the other top-level domains
   (especially COM) and ideas are being considered for restructuring.

   Other names sometimes appear as top-level domain names.  Some people
   have made up names in the DNS-style without coordinating or
   registering  with the DNS management.  Some names that typically
   appear are BITNET, UUCP, and two-letter codes for continents, such as



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   "NA" for North America (this conflicts with the official Internet
   code for Namibia).

   For example, the DNS-style name "KA7EEJ.CO.USA.NA" is used in the
   amateur radio network.  These addresses are never supposed to show up
   on the Internet but they do occasionally.  The amateur radio network
   people created their own naming scheme, and it interferes sometimes
   with Internet addresses.

   1.3  The US Domain

   The US Domain is an official top-level domain in the DNS of the
   Internet community.  The domain administrators are Jon Postel and Ann
   Westine Cooper at the Information Sciences Institute of the
   University of Southern California (USC-ISI).

   US is the ISO-3166 2-letter country code for the United States and
   thus the US Domain is established as a top-level domain and
   registered with the InterNIC the same way other country domains are.

   Because organizations in the United States have registered primarily
   in the EDU and COM domains, little use was initially made of the US
   domain.  In the past, the computers registered in the US Domain were
   primarily owned by small companies or individuals with computers at
   home.  However, the US Domain has grown and currently registers hosts
   in federal government agencies, state government agencies, K12
   schools, community colleges, technical/vocational schools, private
   schools, libraries, city and county government agencies, to name a
   few.

   Initially, the administration of the US Domain was managed solely by
   the Domain Registrar.  However, due to the increase in registrations,
   administration of subdomains is being delegated to others.

   Any computer in the United States may be registered in the US Domain.

2. NAMING STRUCTURE

   The US Domain hierarchy is based on political geography.  The basic
   name space under US is the state name space, then the "locality" name
   space, (like a city, or county) then organization or computer name
   and so on.

   For example:

          BERKELEY.CA.US
          PORTLAND.WA.US




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   There is of course no problem with running out of names.

   The things that are named are individual computers.

   If you register now in one city and then move, the database can be
   updated with a new name in your new city, and a pointer can be set up
   from your old name to your new name.  This type of pointer is called
   a CNAME record.

   The use of unregistered names is not effective and causes problems
   for other users.  Inventing your own name and using it without
   registering is not a good idea.

   In addition to strictly geographically names, some special names are
   used, such as FED, STATE, AGENCY, DISTRICT, K12, LIB, CC, CITY, and
   COUNTY.  Several new name spaces have been created, DNI, GEN, and
   TEC, and a minor change under the "locality" name space was made to
   the existing CITY and COUNTY subdomains by abbreviating them to CI
   and CO.  A detailed description follows.

   Below US, Parallel to States:
   -----------------------------

   "FED" - This branch may be used for agencies of the federal
   government.  For example: <org-name>.<city>.FED.US

   "DNI" - DISTRIBUTED NATIONAL INSTITUTES - The "DNI" branch was
   created directly under the top-level US.  This branch is to be used
   for distributed national institutes; organizations that span state,
   regional, and other organizational boundaries; that are national in
   scope, and have distributed facilities.  For example:
   <org-name>.DNI.US.

   Name Space Within States:
   ------------------------

   "locality" - cities, counties, parishes, and townships.  Subdomains
   under the "locality" would be like CI.<city>.<state>.US,
   CO.<county>.<state>.US, or businesses. For example:
   Petville.Marvista.CA.US.

   "CI" - This branch is used for city government agencies and is a
   subdomain under the "locality" name (like Los Angeles). For example:
   Fire-Dept.CI.Los-Angeles.CA.US.

   "CO" - This branch is used for county government agencies and is a
   subdomain under the "locality" name (like Los Angeles).  For example:
   Fire-Dept.CO.San-Diego.CA.US.



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   "K12" - This branch may be used for public school districts.  A
   special name "PVT" can be used in the place of a school district name
   for private schools.  For example: <school-name>.K12.<state>.US and
   <school-name>.PVT.K12.<state>.US.

   "CC" - COMMUNITY COLLEGES - This branch was established for all state
   wide community colleges.  For example: <school-name>.CC.<state>.US.

   "TEC" - TECHNICAL AND VOCATIONAL SCHOOLS - The branch "TEC" was
   established for technical and vocational schools and colleges. For
   example: <school-name>.TEC.<state>.US.

   "LIB" - LIBRARIES (STATE, REGIONAL, CITY, COUNTY) - This branch may
   be used for libraries only.  For example:  <lib-name>.LIB.<state>.US.

   "STATE" - This branch may be used for state government agencies.  For
   example:  <org-name>.STATE.<state>.US.

   "GEN" - GENERAL INDEPENDENT ENTITY - This branch is for the things
   that don't fit easily into any other structure listed -- things that
   might fit in to something like ORG at the top-level.  It is best not
   to use the same keywords (ORG, EDU, COM, etc.) that are used at the
   top-level to avoid confusion.  GEN would be used for such things as,
   state-wide organizations, clubs, or domain parks.  For example:
   <org-name>.GEN.<state-code>.US.

   ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

   VIEW OF SECOND LEVEL DOMAINS UNDER US

                            +-------+