rfc1386.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

Network Working Group                                          A. Cooper
Request for Comments: 1386                                     J. Postel
                                                           December 1992
                             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 ............................................  5
       2.2  City Codes or Locality Names............................  5
       2.3  Examples of Names.......................................  5
   3.  Registration ................................................  8
       3.1  Requirements ...........................................  8
       3.2  Direct Entries .........................................  9
       3.2.1   UUCP Hosts ..........................................  9
       3.2.2   Non-IP Hosts ........................................ 10
       3.3  Delegated Subdomains ................................... 12
       3.3.1   Schools ............................................. 12
       3.3.2   State Agencies ...................................... 14
       3.3.3   Federal Agencies .................................... 14
       3.3.4   Delegation Requirement............................... 14
       3.3.5   Delegation Procedures ............................... 15
       3.3.6   Subdomain Contacts................................... 18
   4.  Database Information......................................... 19
       4.1  Name Servers ........................................... 19
       4.2  Zone files ............................................. 20
       4.3  Resource Records ....................................... 21
       4.3.1   A Records ........................................... 22
       4.3.2   CNAME Records ....................................... 22
       4.3.3   MX Records .......................................... 22
       4.3.4   HINFO Records ....................................... 23
       4.3.5   PTR Records ......................................... 23
       4.4  Wildcards .............................................. 23
   5.  References .................................................. 24
   6.  Security Considerations ..................................... 25
   7.  Author's Address ............................................ 25
   Appendix-I:  US Domain Names BNF................................. 26
   Appendix-II: US Domain Questionnaire for Host Entry.............. 28



Cooper & Postel                                                 [Page 1]

RFC 1386                     The US Domain                 December 1992


1. INTRODUCTION

   1.1 The Internet Domain Name System

   The Domain Name System (DNS) provides for the translation between
   host names 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 assigned by the Network Information Center
   ([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 registration 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 host name to address mappings were maintained by the
   Network Information Center (NIC) in a single file, called HOSTS.TXT,
   which was FTPed by all the hosts on the Internet.  The network
   population was changing in character.  The timeshared 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 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 hierarcy levels.  A design using a
   distributed database and generalized resources was implemented.

   The domain system provides standard formats for resource data,



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RFC 1386                     The US Domain                 December 1992


   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.

   Even though the intention was that any educational institution any
   where 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, similiary 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 it's own way about organizing its domain, and many
   have.

   Their are no plans of putting all of the organizational domains .EDU
    .GOV .COM etc., under .US.

   However, there are some states registered in the .GOV domain (11 by 2
   letter code), and 3 by full names)

           ca.gov          la.gov          ohio.gov        va.gov
           co.gov          md.gov          or.gov          wa.gov
           hawaii.gov      nc.gov          sc.gov
           ia.gov          ny.gov          texas.gov

   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 ".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.








Cooper & Postel                                                 [Page 3]

RFC 1386                     The US Domain                 December 1992


   1.3  The US Domain

   The US Domain is an official top-level domain in the DNS of the
   Internet community.  It is registered with the Network Information
   Center.  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 NIC 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, private schools, libraries, county agencies, and
   city utilities, to name a few.

   The administration of the US Domain was managed solely by the Domain
   Registrar in the past.  However, due to the increase of hosts,
   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
   namespace under .US is the state namespace, then the city namespace,
   then organization or computer name and so on.

   For example:

          SPK.WA.US
         VANC.WA.US

   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.



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RFC 1386                     The US Domain                 December 1992


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

   2.1  State Codes

   The state codes are the two letter US Postal abbreviations.

   2.2  City Codes or Locality Names

   Cities may be named (designated) by their full name (spelled out with
   hyphens replacing spaces (e.g., Los-Angeles or New-York)), or by a
   city code.  The first choice is the full city name, the second choice
   is the city codes from Western Union's "City Mnemonics" list, and a
   third choice is a code for your city chosen by the applicant.
   However, it is very desirable that all users in the same city use the
   same designator for the city.

   Abbreviated city names are a good idea, particularly when the city
   name is long, as there is much to type already.  One of the problems
   is that the city codes in the Western Union City Mnemonics list are
   sometimes not very good abbreviations.  Users sometimes tend to
   prefer abbreviations that are commonly used already from that region.
   Such as SF for San Francisco, MPK for Menlo Park.

   Exceptions have been made in the abbreviations, even though this
   causes extra work to keep track of these abbreviations.  One
   abbreviation for one city.  Applicants are told what codes are
   currently in use, however, if a city code is not used yet, and they
   would prefer to use a different code that is more common among the
   natives, then the new code is allowed.  However, once it's
   registered, then everyone else who registers in that city will have
   to use that code or spell out the full city name.

   Some applicants have tried to get a copy of the Western Union City
   Mnemonics code list but it is no longer available from Western Union.
   However, we do have a copy but it is not online. If you are
   requesting an abbreviated city code please let us know and we will
   gladly look it up for you.

   2.3  Examples of Names

   For small entities like individuals or small businesses there is
   usually no problem with selecting locality based names.

         For example:  Zuckys.Santa-Monica.CA.US





Cooper & Postel                                                 [Page 5]

RFC 1386                     The US Domain                 December 1992


   For large entities like large corporations with multiple facilities
   in several cities or states this often seems like a unreasonable
   constraint (especially when compared with the alternative of
   registering directly in the .COM domain).  However, a company does
   have a headquarters office in a particular locality and so could
   register with that name.

         For example:  IBM.Armonk.NY.US


             EXAMPLES OF THE NAMING STRUCTURE IN THE US DOMAIN

   PRIVATE (business or individual)
   ================================

   Camp-Curry.Yosemite.CA.US       <====  a business
   IBM.Armonk.NY.US                <====  a business
   Dogwood.atl.GA.US               <====  a business
   Geo-Petrellis.Culver-City.CA.US <====  a restaurant
   Zuckys-Santa-Monica.CA.US       <====  a restaurant
   Joe-Josts.Long-Beach.CA.US      <====  a bar
   Holodek.Santa-Cruz.CA.US        <====  a personal computer

   FEDERAL
   =======

   Senate.FED.US           <====  US Senate
   DOD.FED.US              <====  US Defense Dept.
   DOT.FED.US              <====  US Transportation Dept.
   USPS.FED.US             <====  US Postal Service
   VA.FED.US               <====  US Veterans Administration
   IRS.FED.US              <====  US Internal Revenue Service
   Yosemite.NPS.Interior.FED.US    <====  a federal agency

   STATE
   =====

   Senate.STATE.MN.US      <====  state Senate
   House.STATE.MN.US       <====  state House of Reps
   MDH.STATE.MN.US         <====  state Health Dept.
   HUD.STATE.CA.US         <====  state House and Urban Dev. Dept.
   DOT.STATE.MN.US         <====  state Transportation Dept.
   Caltrans.STATE.CA.US    <====  state Transportation Dept.
   DMV.STATE.CA.US         <====  state Motor Vehicles Dept.
   Culver-City.DMV.STATE.CA.US  <====  a local office of DMV






Cooper & Postel                                                 [Page 6]

RFC 1386                     The US Domain                 December 1992


   CITY | COUNTY
   ==============

   Police.CITY.Culver-City.CA.US       <====  a city department
   Fire-Dept.CITY.Los-Angeles.CA.US    <====  a city department
   Fire-Dept.COUNTY.Los-Angeles.CA.US  <====  a county department