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



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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
  ([email protected]).

  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.








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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





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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






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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

  REGIONAL | DISTRICT | LIBRARY
  =============================

  SCAQMD.DISTRICT.CA.US                     <====  a regional district
  Bunker-Hill-Improvement.DISTRICT.LA.CA.US <====  a local district

  Huntington.LIB.LA.US                    <====  a private library
  Venice.LA-City.LIB.CA.US                <====  a city library
  MDR.LA-County.LIB.CA.US                 <====  a county library

  K12 | CC | STATE UNIV | PRIVATE SCHOOLS
  =======================================

  Los-Angeles.UC.STATE.CA.US      <====  UCLA
  Berkeley.UC.STATE.CA.US         <====  "CAL"
  Irvine.UC.STATE.CA.US           <====  University of Calif. Irvine
  Santa-Cruz.UC.STATE.CA.US       <====  University of Calif. Santa Cruz
  Northridge.CSU.STATE.CA.US      <====  Calif. State. Univ. Northridge
  Fullerton.CSU.STATE.CA.US       <====  Calif. State. Univ. Fullerton
  Sonoma.CSU.STATE.CA.US          <====  Calif. State. Univ. Sonoma

  SMCC.Santa-Monica.CC.CA.US      <====  a public community college
  Trade-Tech.Los-Angeles.CC.CA.US <====  a public community college

  Hamilton.High.LA-Unified.K12.CA.US      <====   a public K12 school
  Sherman-Oaks.Elem.LA-Unified.K12.CA.US  <====   a public K12 school
  John-Muir.Middle.Santa-Monica.K12.CA.US <====   a public K12 school

  St-Monica.High.Santa-Monica.CA.US       <====  a private high school
  St-Monica.Elem.Santa-Monica.CA.US       <====  a private elem. school
  Crossroads-School.Santa-Monica.CA.US    <====  a private school
  Mary-Ellens.Montessori-School.LA.CA.US  <====  a private school
  Leland-Stanford-Jr-Univ.Stanford.CA.US  <====  a private school
  Loyola-Marymount-Univ.Los-Angeles.CA.US <====  a private school










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RFC 1386                     The US Domain                 December 1992


  When appropriate, subdomains are delegated and partioned in various
  categories, such as:

                  K12.<state>.US   =   kindegarten thru 12th grade
                   CC.<state>.US   =   community colleges
                  LIB.<state>.US   =   libraries
                STATE.<state>.US   =   state government agencies
               <org-name>.FED.US   =   federal government agencies

  The Appendix-I contains the current US Domain Names BNF, but in
  actuality, the names under these subdomains may vary according to the
  decision of the administrators of these subdomains.

  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 host name.  Cities and in some cases counties are used.

3. REGISTRATION

  3.1  Requirements

  Anyone requesting to register a host in the US Domain is sent a copy
  of the US Domain policy and procedure, and must fill out a US Domain
  questionnaire.

  The US Domain template, is similar to the NIC Domain template
  however, it is not the same.  To request a copy of the US Domain
  questionnaire, send a message to the US Domain registrar (us-
  [email protected]).

     Note:  If you are registering a name in a delegated zone
            (see Section 3.3.6).  Please register with the
            contact for that zone.

  The key people must have electronic mailboxes (that work).  Please
  provide all the information indicated in the "Administrator" and
  "Technical Contact" slot.  This person will be the point of contact
  for any administrative and policy questions about the domain.

  The administrator is usually the person who manages the organization
  being registered. The technical contact can also be administrator, or
  the systems person, or someone who is familiar with the technical
  details of the Internet. The technical contact should have a valid
  working e-mail address. This is necessary in case something goes
  wrong.




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RFC 1386                     The US Domain                 December 1992


  It is important that your "Return-Path" and "From" field indicate an
  Internet style address.  UUCP style addresses such as "host1!user"
  will not work. This is fine within the UUCP world, but not the
  Internet.  If you want people on the Internet to be able to send mail
  to you, your return path needs to be an Internet style address: such
  as [email protected] or [email protected].

  It is also possible to register through one of the Internet service
  providers that have established working relationships with the US
  domain administrator.

  If everything checks out, turn around time for registering a host is
  usually a day or two.  The nameservers are updated anywhere from 12
  to 24 hours later.

  There are two ways to be registered in the US Domain, directly, or by
  delegation.

  3.2  Direct Entries

  Direct entry in the database of the US Domain appeals most to
  individuals and small companies.  Fill out the application and send
  it directly to the US Domain administrator.  If you are in an area
  where the zone is delegated to someone else your request will be
  forwarded to the zone administrator for your registration.

  3.2.1 UUCP Hosts

  Many applicants have hosts in the UUCP world.  Some are one hop away,
  some two and three hops away from their "Internet Forwarder", this is
  ok.  What is important is getting an Internet host to be your
  forwarder.  If you do not already have an Internet forwarder, there
  are several businesses that provide this service for a fee, such as
  UUNET.UU.NET ([email protected]), PSI ([email protected])
  and CERFNET ([email protected]).  Sometimes local colleges in your area
  are already on the Internet and may be willing to act as an Internet
  Forwarder.  You would need to work this out with the systems
  administrator we cannot make these arrangements for you.

  Although we work with UUCP service providers, the Internet US Domain
  registration is not affiliated with the registration of UUCP Map
  entries.  The UUCP map entry does not provide us with sufficient
  information.  If you do not have a copy of the US Domain
  questionnaire template, please send a message to: [email protected]
  and request one.  See Appendix-II.






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RFC 1386                     The US Domain                 December 1992


  This is not an appropriate registration for the US Domain.

    #N starl
    #S Amiga 2500; AmigaDOS 2.04; Dillon's AmigaUUCP 1.15D
    #O Starlight BBS
    #C Stephen Baker
    #E starl!sbaker
    #T +1 305 378 1161
    #P 1107 SW 200th St #303B Miami, Fl. 33157
    #L 25 47 N / 88 10 W [city]
    #R
    #U mthvax
    #W starl!sbaker (Stephen Baker); Mon Feb 24 19:58:24 EST 1992
     starl        mthvax(DAILY)

  If you are registering your host as a central site for a USENET group
  where other UUCP sites will feed from you, that's fine.  These UUCP
  sites do not need to register.  If however, the other sites become a
  subdomain of your hostname, then we will need to register them
  individually or add a wildcard record.

          For example:          bah.rochester.ny.us
                          host1.bah.rochester.ny.us
                          host2.bah.rochester.ny.us

  3.2.2 NON-IP Hosts

  To use US Domain names for non-IP hosts, there must be a forwarder
  host that is an IP host.  There must be an adminstrative agreement
  and a technical procedure for relaying mail between the non-IP host
  and the forwarder host.

  Case 1:
  -------

  Your host is not an IP host but does talk directly with a host that
  is an IP host.
                                                 +-----------------+
  +----------+            +---------+            |                 |
  |your-host |---UUCP-----|forwarder|----IP/TCP--|    INTERNET     |
  +----------+            +---------+            |                 |
                                                 +-----------------+
  "Forwarder" must be an IP host on the Internet.

  You must ask "forwarder" if they are willing to be the internet
  forwarder for "your-host".

  In the US Domain of the DNS data base there must be an entry like



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  this:
         "your-host"  MX  10  "forwarder"

  This must be entered by the US Domain administrator.

  In the "forwarder" routing tables there must be information about
  "your-host" with a rule like: If I see mail for "your-host" I will
  send it via uucp by calling phone number "123-4567".

  Case 2:
  -------

  In this case your hosts talks to another host that ... that talks to
  an IP host.  In other words, there are multiple hops between your host
  and the Internet.
                                                 +-----------------+
  +----------+            +---------+            |                 |
  |path-host |---UUCP-----|forwarder|----IP/TCP--|    INTERNET     |
  +----------+            +---------+            |                 |
      |                                          +-----------------+
     UUCP
      |
  +----------+
  |your-host |
  +----------+

  "Forwarder" must be an IP host on the internet.

  You must ask "forwarder" if they are willing to be the Internet
  Forwarder for "Your-Host".  You must ask "path-host" to relay your
  mail.

  In the US Domain of the DNS DataBase there must be an entry like this:

         "your-host"  MX  10  "forwarder"

  This must be entered by the US Domain Administrator.

  In the "forwarder" routing tables there must be information about
  "your-host" with a rule like: If I see mail for "your-host" I will
  send it via UUCP to "path-host" by calling phone number "123-4567".
  and "path-host" must also know how to relay the mail to "your-host".

  Note: It is assumed that "path-host" is already MXed to "forwarder".
  It is not appropriate to ask to MX "your-host" to "path-host" (this
  is sometimes called double MXing).  The host on the right hand side
  of an MX entry must be a host on the Internet with an IP address
  (e.g., 128.9.2.32).



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RFC 1386                     The US Domain                 December 1992


  3.3  Delegated Subdomains

  The administrator of the US Domain is responsible for the assignment
  of all the DNS names that end with ".US".  Of course, one person or
  even one group can't handle all this in the long run so portions of
  the name space are delegated to others.

  Delegation of cities, companies within cities, schools (K12),
  community colleges (CC), libraries (LIB), state government (STATE),
  and federal government agencies, departments, etc., is acceptable and
  practical.

  For a delegated portion of the namespace, for example a city, no
  alterations can be made to that name, no abbreviations added, etc.
  unless applied for.

  Sometimes there may be two people running name servers in the same
  city because different portions of the name space has been delegated
  to them.  For example, someone may be delegated the <city>.<state>.US
  name space, and someone else from a state government agency may have
  the .STATE.<state>.US, portion.  For example, Fred may run the name
  servers for Sacramento.CA.US and Joe may run the name servers for
  STATE.CA.US in Sacramento.

  If a company would like to have wildcard records added, or run their
  own name servers in a city that we have delegated name space to, this
  is ok.

  Delegation of the whole State namespace is not yet implemented.  The
  delegated part of the name space is in the form of:

                   .STATE.<state>.US.
                     .K12.<state>.US.
                      .CC.<state>.US.
                     .LIB.<state>.US.
       .<org-name>.<city>.<state>.US.
        .CITY.<city-name>.<state>.US.
                  .<org-name>.FED.US.

  3.3.1  Schools

  As schools begin to join the Internet, there ought to be a consistent
  scheme for naming them.  A "K12" name branch has been established in
  each state in the US Domain for this purpose.

  Public schools are usually organized by districts which can be larger
  or smaller than a city or county.




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RFC 1386                     The US Domain                 December 1992


  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.

  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 when they are needed, if the school's name is
  unique without such keywords don't use them.

  Typical K12 school names currently used are like:

             IVY.PRS.K12.NJ.US
             DMHS.JCPS.K12.KY.US
             OHS.EUNION.K12.CA.US
             BOHS.BREA.K12.CA.US

  These names could be long.  Given the large number of schools,
  organizing by school district and state seems appropriate.  When
  there are many things to name some of the names must be long.

  In some cases there may be appropriate abbreviations that can be
  used.  For example Hamilton High School in Los Angeles could be:

             Hami.Hi.LA.K12.CA.US

     Some School Examples:
     ---------------------

     Hamilton.High.LA-Unified.K12.CA.US        <== a public school
     Sherman-Oaks.Elem.LA-Unified.K12.CA.US    <== a public school
     John-Muir.Middle.Santa-Monica.K12.CA.US   <== a public school
     Crossroads-School.Santa-Monica.CA.US      <== a private school
     SMCC.CC.CA.US                             <== a community college
     Northridge.CSU.STATE.CA.US                <== a state university

  If a school has a bunch of PCs, then each PC should have a name.
  Suppose they are named "alpha", "beta", ... then if they belong to a
  school named "Lincoln.High.Lakewood.K12.CA.US" their names would be:

               alpha.Lincoln.High.Lakewood.K12.CA.US.
               beta.Lincoln.High.Lakewood.K12.CA.US
          ...






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RFC 1386                     The US Domain                 December 1992


  3.2.2  State Agencies

  US Domain namespace has been delegated to the state goverment
  agencies.  For example, in the State of Minnesota, the subdomain is
  STATE.MN.US

  This means that the person running the namservers for state.mn.us are
  responsible for naming agencies, of the state govermnent.  For
  example:

     State Agencies:
     ---------------

     Senate.STATE.MN.US      <== State Senate
     MDH.STATE.MN.US         <== Dept. of Health
     CALTRANS.STATE.CA.US    <== Dept. of Transportation
     DMV.STATE.CA.US         <== Dept. of Motor Vehicles

  3.3.3  Federal Agencies

  A federal namespace has been delegated to the federal government
  agencies.  For example the subdomain for the Federal Reserve Bank of
  Minneapolis is MNPL.FRB.FED.US. Other examples are listed below.

     Federal Government Agencies:
     ---------------------------

     Senate.FED.US   <====  US Senate
     DOD.FED.US      <====  US Defense 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

  3.3.4  Delegation Requirements

  When a subdomain is delegated, the following requirements must be
  met:

     1)  There must be a knowledgeable and competent technical contact,
         familiar with the Internet Domain Name System.  This
         requirement is easily satisified if the technical contact
         already runs some other nameservers.

     2)  Organizations requesting delegations must provide at least two
         independent (robust and reliable) DNS name servers in
         physically separate locations on the Internet.




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RFC 1386                     The US Domain                 December 1992


     3)  The subdomain must accept all applicants on an equal basis.

     4)  The subdomain must provide timely processing of requests.  To
         do this it is helpful to have several individuals
         knowledgeable about the procedures so that the operations are
         not delayed due to one persons unavailability (for example by
         being on vacation).

  3.3.5  Delegation Procedures

  The procedure that is followed when a subdomain is delegated includes
  the following steps:

     1)  Evaluate the technical contact's experience with DNS.  Make
         sure there is a need for the proposed delegation.  Make sure
         the technical contact has the information about the US Domain
         and the suggested naming structure.

     2)  Note: In the past there was the concept of a "coordinator" for
         a group or a club or "Domain Park". They would arrange to
         coordinate the registration of all the computers used by
         members of the club and forward all the information for the
         group to the US Domain Administrator.  Most coordinators have
         moved into the position of administrator of that now delegated
         subdomain.

     3)  Add the new technical contact to the "us-dom-adm" mailing list
         for distributing updates to the US Domain policies and
         procedures, or other pertinent information.

     4)  Delete any hosts from our zone file that belongs in the newly
         delegated subdomain and make sure they now have the hosts in
         their zone file.


















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RFC 1386                     The US Domain                 December 1992


     5)  Send them a copy of the zone file so their initial zone file
         is identical to ours. For example:

           mil.wi.us.   86400   SOA spool.mu.edu. manager.spool.mu.edu. (
                                   920904  ;serial
                                   28800   ;refresh
                                   14400   ;retry
                                   3600000 ;expire
                                   86400 ) ;minim

           mil.wi.us.      86400   NS      spool.mu.edu.
           spool.mu.edu.   50400   A       134.48.1.31
           mil.wi.us.      86400   NS      sophie.mscs.mu.edu.

           sophie.mscs.mu.edu.     50400   A       134.48.4.6
           solaria.mil.wi.us.      86400   HINFO   Sun 3/60 SunOs
           solaria.mil.wi.us.      86400   MX      10 spool.mu.edu.
           nthomas.mil.wi.us.      86400   HINFO   386 Clone DOS
           nthomas.mil.wi.us.      86400   MX      10 spool.mu.edu.
           rwmke.mil.wi.us.        86400   HINFO   UNIX PC UNIX
           rwmke.mil.wi.us.        86400   MX      10 spool.mu.edu.
           milestn.mil.wi.us.      86400   HINFO   PC AT ENIX
           milestn.mil.wi.us.      86400   MX      10 spool.mu.edu.
           dawley.mil.wi.us.       86400   HINFO   386 Clone DOS
           dawley.mil.wi.us.       86400   MX      10 spool.mu.edu.
           ...
                     -------------------------------------
























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RFC 1386                     The US Domain                 December 1992


     6)  The US Domain zone file must have the following records,
         showing the name, address, e-mail, and phone number of the
         technical contact for the delegated subdomain and the name of
         the delegated name space and the names of the nameservers.

           ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
           ;
           ;Delegated zone: .mil.wi.us
           ;Contact:  Steven Goodman
           ;          [email protected]
           ;          Marquette University
           ;          (414) 288-6734

           mil.wi.us.      604800  NS      SPOOL.MU.EDU.
                           604800  NS      SOPHIE.MSCS.MU.EDU.

           ; A glue record is not needed this time. Glue records are
           ; needed when the name of the server is a subdomain of the
           ; delegated domain.
           ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

     7)  Check to see that delegated subdomain name servers are up and
         running, and make sure the delegated hosts are installed in
         their zone file.  Now delete any hosts from the US Domain zone
         file that belongs in the newly delegated subdomain.

     8)  Inform the technical contact of the newly delegated subdomain
         that wildcard records are allowed in the zone file under the
         organizational subdomain but no wildcard records are allowed
         under the "city" or "state" domain.





















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RFC 1386                     The US Domain                 December 1992


  3.3.6   Subdomain Contacts

  Approximately 680 individual hosts are registered, but we have
  delegated the following portions of the namespace.  We do not know
  how many hosts are registered under each of these subsdomains.

          DELEGATED ZONE             CONTACT
          ==============             =======

          TUCSON.AZ.US               [email protected]
          SF.CA.US                   [email protected]
          PREMENOS.SF.CA.US          [email protected]
          SCVL.CA.US                 [email protected]
          SANTA-CRUZ.CA.US           [email protected]
          APTOS.CA.US                [email protected]
          CAMPBELL.CA.US             [email protected]
          CAPITOLA.CA.US             [email protected]
          FELTON.CA.US               [email protected]
          ZAYANTE.CA.US              [email protected]
          BOULDER-CREEK.CA.US        [email protected]
          DARWIN.PTVY.CA.US          [email protected]
          LOGAN-HS.UNIONCITY.CA.US   [email protected]
          BOULDER.CO.US              [email protected]
          COLOSPGS.CO.US             [email protected]
          DENVER.CO.US               [email protected]
          DVR.CO.US                  [email protected]
          CHI.IL.US                  [email protected]
          EUGENE.OR.US               [email protected]
          SPRINGFIELD.OR.US          [email protected]
          MULTNOMAH.LIB.OR.US        [email protected]
          PGH.PA.US                  [email protected]
          SPK.WA.US                  [email protected]
          MIL.WI.US                  [email protected]
          ATL.GA.US                  [email protected]
          Mt-PARK.GA.US              [email protected]
          CLARKSTON.GA.US            [email protected]
          STATE.MN.US                [email protected]
          MNPL.FRB.FED.US            [email protected]

          K12.CA.US                  [email protected]
          CC.CA.US                   [email protected]
          K12.MI.US                  [email protected]
          K12.TX.US                  [email protected]
          K12.NJ.US                  [email protected]
          K12.MS.US                  [email protected]
          dmhs.jcps.K12.KY.US        [email protected]
          TIES.K12.MN.US             [email protected]




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RFC 1386                     The US Domain                 December 1992


       The following MD.US counties have been delegated to
       ([email protected]).

          AL.MD.US.       Allegany
          AA.MD.US.       Anne Arundel
          BA.MD.US.       Baltimore
          CAL.MD.US.      Calvert
          CAR.MD.US.      Caroline
          CE.MD.US.       Cecil
          CH.MD.US.       Charles
          DO.MD.US.       Dorchester
          FR.MD.US.       Frederick
          GA.MD.US.       Garrett
          HA.MD.US.       Harford
          HO.MD.US.       Howard
          KE.MD.US.       Kent
          MO.MD.US.       Montgomery
          PG.MD.US.       Prince George"s
          QA.MD.US.       Queen Anne's
          SM.MD.US.       St. Mary's
          SO.MD.US.       Somerset
          TA.MD.US.       Talbot
          WA.MD.US.       Washington
          WI.MD.US.       Wicomico
          WO.MD.US.       Worcester

4. DATABASE INFORMATION

  4.1. Name Servers

  Name servers are the repositories of information that make up the
  domain database.  The database is divided up into sections called
  zones, which are distributed among the name servers.  While name
  servers can have several optional functions and sources of data, the
  essential task of a name server is to answer queries using data in
  its zones.  The response to a query can always be generated using
  only local data, and either contains the answer to the question or a
  referral to other name servers "closer" to the desired information.

  A given zone will be available from several name servers to insure
  its availability in spite of host or communication link failure.
  Every zone is required to be available on at least two servers, and
  many zones have more redundancy than that.








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RFC 1386                     The US Domain                 December 1992


  The US Domain is currently supported by six name servers.

          venera.isi.edu
          ns.isi.edu
          ns.hercules.csl.sri.com
          nnsc.nsf.net
          ns.uu.net
          adm.brl.mil

  4.2 Zone Files

  A "zone" is a registry of domains kept by a particular organization.
  A zone registry is "authoritative", that is, the master copy of the
  registry is kept by the zone organization, and this copy is, by
  definition, always up-to-date.  Copies of this registry may be
  distributed to other places and kept in caches, but these caches are
  not authoritative, and may be out-of-date.

  Every zone has at least one node, and hence domain name, for which it
  is authoritative, and all of the nodes in a particular zone are
  connected.  Given the tree structure, every zone has a highest node
  which is closer to the root than any other node in the zone.  The
  name of this node is often used to identify the zone.  The data that
  describes a zone has four major parts:

       1) Authoritative data for all nodes within the zone.

       2) Data that defines the top node of the zone
          (can be thought of as part of the authoritative data).

       3) Data that describes delegated subzones, i.e., cuts
          around the bottom of the zone,

       4) Data that allows access to name servers for subzones
          (sometimes called "glue" data).

  The zone administrator has to maintain the zones at all the
  namservers which are authoritative for the zone.  When the changes
  are made they must be distributed to all of the name servers.

  Copies of the zone files are not available unless you are on the
  Internet.  To look at the zone files use the "dig" program of the DNS
  domain name system.

       dig   @nshost  host-your-checking  axfr






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RFC 1386                     The US Domain                 December 1992


  4.3 Resource Records

  Records in the zone data files are called resource records (RRs).
  The standard Resource records (RR) are specified in STD 13, RFC 1034
  and STD 13, RFC 1035 (3,4).  An RR has a standard format as shown.

                 <name> [<ttl>] [<class>] <type> <data>

  The first field is always the name of the domain record.  The second
  field is an optional time to live field.  This specifies how long
  this data will be stored in the data base.  The third field is the
  address class; the class field specifies the protocol group most
  often this is the Internet class "IN".  The fourth field states the
  type of the resource record.  The fields after that are dependent on
  the Type of RR. The fifth field is the data field which is defined
  differently for each type and class of data.  Here is a list of the
  current commonly used types.

          SOA     Start of Authority
          NS      Name Server
          A       Internet Address
          CNAME   Canonical Name (nickname pointer)
          HINFO   Host Information
          WKS     Well Known Services
          MX      Mail Exchanger
          PTR     Pointer

  What do the fields mean?

          foo.LA.CA.US.    604800    MX   10     Venera.ISI.EDU.
          (1)              (2)       (3)  (4)    (5)

          1)  domain name
          2)  time to live information
          3)  mail exchanger record
          4)  preference value to determine (if more than one
              forwarder) which mailer to use first, lower number
              higher preference
          5)  the Internet forwarding host.












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RFC 1386                     The US Domain                 December 1992


  4.3.1  A Records

  Internet (IP) Address.  The data for an "A" record is an Internet
  address in a dotted decimal form.  A sample "A" record might look
  like:

          venera.isi.edu.          A      128.9.0.32
             (name)               (A)     (address)

  The name field is the machine name, and the address is the network
  address. There should be only one "A" record for each address of a
  host.

  4.3.2  CNAME Records

  Canonical Name resource record, CNAME, specifies an alias for a
  canonical name. This is essentially a pointer to the official name
  for the requested name.  All other RRs appear under this official
  name.  A machine named FERNWOOD.MPK.CA.US may want to have the
  nickname ANTERIOR.MPK.CA.US.  In that case, the following RR would be
  used:

          anterior.mpk.ca.us.     CNAME      fernwood.mpk.ca.us.
           (alias nickname)                   (canonical name)

  Nicknames (the name associated with the RR is the nickname) may be
  added for awhile when a host changes its name, usually because it
  moves to another state.  It helps to have this CNAME pointer so if
  any mail comes to the old address it will get forwarded to the new
  one.  There cannot be any other RRs associated with a nickname of the
  same class.

  4.3.3  MX Records

  Mail Exchanger records, MX, are used to specify a machine that knows
  how to deliver mail to a machine that is not directly connected to
  the Internet.  For example, venera.isi.edu is the mail gateway that
  knows how to deliver mail to foo.la.ca.us, but other machines on the
  network cannot deliver mail directly to foo.la.ca.us.  These two
  machines may have a private connection or use a different transport
  medium (such as uucp).  The preference value (10) is the order that a
  mailer should follow when there is more than one way to deliver mail
  to a single machine.  The lower the number the higher the preference.

          foo.LA.CA.US.  604800  MX  10  Venera.ISI.EDU.
          foo.LA.CA.US.  604800  MX  20  relay1.uu.net.





Cooper & Postel                                                [Page 22]

RFC 1386                     The US Domain                 December 1992


  4.3.4   HINFO Records

  Host information resource records, HINFO is for host specific data.
  This lists the hardware and operating system that are running at the
  listed host.  It should be noted that a space separates the hardware
  information and the operating system information.  If you want to
  include a space in the machine name you must quote the name.  Host
  information is not specific to any class, so ANY may be used for the
  address class.  There should be one HINFO record for each host.

  acb.la.ca.us.       HINFO       VAX-11/780      UNIX
                                  (Hardware)      (Operating System)

  The official HINFO types can be found in the latest Assigned Numbers
  RFC, the most recent edition being RFC 1340.  The hardware type is
  called the Machine Name, and the software type is called the System
  Name.

  The information users supply about this is often inconsistent or
  incomplete.  Please follow the terms in the current "Assigned
  Numbers".

  4.3.5  PTR Records

  A Domain Name Pointer record, PTR, allows special names to point to
  some other location in the domain data base.  These are typically
  used in setting up reverse pointers for the special IN-ADDR.ARPA
  domain.  PTR names should be unique to the zone.

        0.0.9.128.in-addr.arpa     PTR    isi-net.isi.edu.
            (special name)                  (real name)

  A PTR record is to be added to the IN-ADDR.ARPA domain for every A
  record registered in the US Domain.  These PTR records need to be
  added by the administrator of the network where the host is
  connected.  The US Domain administration does not administer the
  network and cannot make these entries in the DNS database.

  4.4  Wildcards

  The wildcard records are of the form "*.<anydomain>", where
  <anydomain> is any domain name.  The wildcards potentially apply to
  descendents of <anydomain>, but not to <anydomain> itself.

  For example, suppose a large company located in California with a
  large, non-IP/TCP, network wanted to create a mail gateway.  If the
  company was called DWP.LA.CA.US, and the IP/TCP capable gateway
  machine (Internet forwarder) was called ELROY.JPL.NASA.GOV, the



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RFC 1386                     The US Domain                 December 1992


  following RRs might be entered into the .US zone.

          dwp.la.ca.us    MX      10       ELROY.JPL.NASA.GOV
        *.dwp.la.ca.us    MX      10       ELROY.JPL.NASA.GOV

  The wildcard record *.DWP.LA.CA.US would cause an MX query for any
  domain name ending in DWP.LA.CA.US to return an MX RR pointing at
  ELROY.JPL.NASA.GOV. The entry without the "*" is needed so the host
  dwp can be found.

  In the US Domain, wildcard records are allowed in our zone files
  under the organizational subdomain (and where noted otherwise) but no
  wildcard records are allowed under the "City" or "State" domain.

      The authors strongly believe that it is in everyone's
      interest and good for the Internet to have each host
      explicitly registered (that is, we believe that wildcards
      should not be used), we also realize that not everyone
      agrees with this belief.  Thus, we will allow wildcard
      records in the US Domain under groups or organizations.
      For example, *.DWP.LA.CA.US.

      The reason we feel single entries are the best is by the mere
      fact that if anyone wanted to find one of the hosts in the
      domain name system it would be there, and problems can be
      detected more easily.  When using wildcards records all the
      hosts under a subdomain are hidden.

5. REFERENCES

  [1]  Stahl, M., "Domain Administrators Guide", RFC 1032, SRI
       International, November 1987.

  [2]  Lottor, M., "Domain Administrators Operations Guide" RFC 1033,
       SRI International, November 1987.

  [3]  Mockapetris, P., "Domain Names - Concepts and Facilities",
       STD 13, RFC 1034, ISI, November 1987.

  [4]  Mockapetris, P., "Domain Names - Implementation and
       Specification", STD 13, RFC 1035, ISI, November 1987.

  [5]  Dunlap, K., "Name Server Operations Guide for Bind,
       Release 4.3", UC Berkeley, SMM:11-3.

  [6]  Partridge, C., "Mail Routing and the Domain Name System",
       STD 14, RFC 974, BBN, January 1986.




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RFC 1386                     The US Domain                 December 1992


6. SECURITY CONSIDERATIONS

  Security issues are not discussed in this memo.

7. AUTHORS' ADDRESSES

  Ann Cooper
  USC/Information Sciences Institute
  4676 Admiralty Way
  Marina del Rey, CA  90292

  Phone:  1-310-822-1511
  Email:  [email protected]


  Jon Postel
  USC/Information Sciences Institute
  4676 Admiralty Way
  Marina del Rey, CA  90292

  Phone:  1-310-822-1511
  Email:  [email protected]





























Cooper & Postel                                                [Page 25]

RFC 1386                     The US Domain                 December 1992


                    APPENDIX-I:  US DOMAIN NAMES BNF
                    ================================

  <us-domain-name>    ::= <us-name><dot><us>

  <us-name>           ::= <state-name><dot><state-code> |
                          <fed-name><dot><fed>

  <state-code>        ::= <the two-letter code of a state from the
                           zip code directory>

  <state-name>        ::= <local-name><dot><locality> |
                          <state-agency-name><dot><state> |
                          <regional-agency-name><dot><agency>

  <fed-name>          ::= <the dotted hierarchical name of a US
                           federal government agency>

  <locality>          ::= <the full name of a city from the
                            zip code directory> |
                          <a short code name for a city> |
                          <the full name of a county, township,
                           or parish> |
                          <other well known and commonly used
                           locality name>

  <local-name>        ::= <entity-name> |
                          <city-name><dot><city> |
                          <county-name><dot><county> |
                          <local-agency-name><dot><agency>

  <state-agency-name> ::= <the dotted hierarchical name of a state
                           government agency>

  <regional-agency-name> ::= <the dotted hierarchical name of a special
                           agency or district not an element of the
                           state government and typically larger than
                           a single city or county, for example, the
                           Southern California Air Quality Management
                           District>

  <entity-name>       ::= <the dotted hierarchical name of an entity
                           within a city, for example: a company,
                           business, private school, club, organization,
                           or individual>

  <city-name>         ::= <the dotted hierarchical name of a city
                           government agency>



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RFC 1386                     The US Domain                 December 1992


  <county-name>       ::= <the dotted hierarchical name of a county,
                            township, or parish government agency>

  <local-agency-name> ::= <the dotted hierarchical name of a special
                           agency or district not an element of a
                           city or county government and typically
                           equal or smaller than a single city or
                           county, for example, the Bunker Hill
                           Improvement District>


  <city> ::= "CITY"

  <county> ::= "COUNTY" | "TOWNSHIP" | "PARISH"

  <dot> ::= "."

  <fed> ::= "FED"

  <agency> ::= "AGENCY" | "DISTRICT" | "K12" | "CC" | "LIB"

  <state> ::= "STATE" | "COMMONWEALTH"

  <us> ::= "US"


  Note:  "K12" may be used for public school districts, only.
         and "CC" may be used only for public community colleges,
         and "LIB" can only be used by libraries.






















Cooper & Postel                                                [Page 27]

RFC 1386                     The US Domain                 December 1992


           APPENDIX-II: US DOMAIN QUESTIONNAIRE FOR HOST ENTRY


To register a host in the US domain, the following information must be
sent to the US Domain Registrar ([email protected]).  Questions may be
sent by electronic mail to the above address, or by phone to
Ann Cooper (310-822-1511).


(1)  The name of the top-level domain to join.

          For example:  US


(2)  The name of the administrative head of the organization, including
    title, mailing address, phone number, organization, and network
    mailbox.  This is the contact point for administrative and policy
    questions about the domain.  In the case of a research project,
    this should be the principal investigator.

          For example:

             Administrator

                Organization  The NetWorthy Corporation
                Name          Penelope Q. Sassafrass
                Title         President
                Mail Address  The NetWorthy Corporation
                              4676 Andrews Way, Suite 100
                              Santa Clara, CA 94302-1212
                Phone Number  (415) 123-4567
                Net Mailbox   [email protected]



















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RFC 1386                     The US Domain                 December 1992


(3)  The name of the technical contact for the entry, including title,
    mailing address, phone number, organization, and network mailbox.
    This is the contact point for problems concerning the domain or
    zone, as well as for updating information about the domain or zone.

          For example:

             Technical Contact

                Organization  The NetWorthy Corporation
                Name          Ansel A. Aardvark
                Title         Executive Director
                Mail Address  The NetWorthy Corporation
                              4676 Andrews Way, Suite 100
                              Santa Clara, CA. 94302-1212
                Phone Number  (415) 123-6789
                Net Mailbox   [email protected]


(4)  The name of the host.  This is the name that will be used in tables
    and lists associating the domain with the domain server addresses.
    [While, from a technical standpoint, domain names can be quite long
    (programmers beware), shorter names are easier for people to cope
    with.]

          For example:  NetWorthy.Santa-Clara.CA.US

          Or:  Alpha.NetWorthy.Santa-Clara.CA.US
               Beta.NetWorthy.Santa-Clara.CA.US


(5)  If this machine is not directly on the internet, how does it
    communicate with the Internet.  Through UUCP, CREN, etc?  Which
    forwarding host?

         For example:  The host "Networthy.Santa-Clara.CA.US" uses UUCP
         to connect to "RELAY.ISI.EDU" which is an Internet host.

         The administrator of RELAY.ISI.EDU must agree to be the
         forwarding host for Networthy.Santa-Clara.CA.US, and the
         forwarding host must know a delivery method and route to it.
         No double MXing.









Cooper & Postel                                                [Page 29]

RFC 1386                     The US Domain                 December 1992


         If you are requesting an indirect connection, that is, a Mail
         Exchanger (MX) record, what is the name and mailbox of the
         administrator of the forwarding host.

         For example:John Smith
              [email protected]


(6)  Please describe your organization briefly.

    For example: The NetWorthy Corporation is a consulting
    organization of people working with UNIX and the C language in an
    electronic networking environment.  It sponsors two technical
    conferences annually and distributes a bimonthly newsletter.


(7)  What Domain Name System (DNS) Resource Records (RR) and values are
    to be entered.

    a.  A       Internet Address (internet hosts only)
    b.  HINFO   Host Information, Machine System
    c.  WKS     Well Known Services, Protocols, Ports (internet hosts only)
    d.  MX      Mail Exchanger (required for UUCP, and CREN hosts)

    An example of RRs for an internet host.

    NetWorthy.Santa-Clara.CA.US   IN   A       128.9.3.123
                             IN   HINFO   SUN-3/11OC UNIX
                             IN   MX      10  ISI.EDU
                             IN   WKS     128.9.3.123. UDP (echo
                                                            tftp)
                             IN   WKS     128.9.3.133. TCP (telnet
                                                            ftp
                                                            tftp
                                                            finger)

    An example of RRs for a non-internet host.

    Beta.NetWorthy.Santa-Clara.CA.US   MX      10   RELAY.ISI.EDU
                                       HINFO   SUN-3/11OC UNIX











Cooper & Postel                                                [Page 30]

RFC 1386                     The US Domain                 December 1992


(8)  Where is the IN-ADDR pointer record to be entered. (For internet
    hosts only.)  It is your responsibility to see that this is done.
    Contact the administrator of the IP network your host is on.  The
    US Domain administration does not administer the network and cannot
    make these entries in the DNS database.

       For example:

          123.3.9.128.IN-ADDR.ARPA.    PTR  NetWorthy.Santa-Clara.CA.US

    Who is the contact for the zone of the IN-ADDR.ARPA data, where
    this record will be entered?


(9)  What Time to Live (TTL)?  TTL is the time (in seconds) that a
    resolver will use the data it got from the domain server before it
    asks it again for the data.  A typical TTL is One Week 604800.
    (NOTE:  TTL is not applicable to non-Internet hosts.)

       For example:

          One Week   604800





























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