`Request for Comments: 1591 ISI
`Category: Informational March 1994
`
` Domain Name System Structure and Delegation
`
`Status of this Memo
`
` This memo provides information for the Internet community. This memo
` does not specify an Internet standard of any kind. Distribution of
` this memo is unlimited.
`
`1. Introduction
`
` This memo provides some information on the structure of the names in
` the Domain Name System (DNS), specifically the top-level domain
` names; and on the administration of domains. The Internet Assigned
` Numbers Authority (IANA) is the overall authority for the IP
` Addresses, the Domain Names, and many other parameters, used in the
` Internet. The day-to-day responsibility for the assignment of IP
` Addresses, Autonomous System Numbers, and most top and second level
` Domain Names are handled by the Internet Registry (IR) and regional
` registries.
`
`2. The Top Level Structure of the Domain Names
`
` In the Domain Name System (DNS) naming of computers there is a
` hierarchy of names. The root of system is unnamed. There are a set
` of what are called "top-level domain names" (TLDs). These are the
` generic TLDs (EDU, COM, NET, ORG, GOV, MIL, and INT), and the two
` letter country codes from ISO-3166. It is extremely unlikely that
` any other TLDs will be created.
`
` Under each TLD may be created a hierarchy of names. Generally, under
` the generic TLDs the structure is very flat. That is, many
` organizations are registered directly under the TLD, and any further
` structure is up to the individual organizations.
`
` In the country TLDs, there is a wide variation in the structure, in
` some countries the structure is very flat, in others there is
` substantial structural organization. In some country domains the
` second levels are generic categories (such as, AC, CO, GO, and RE),
` in others they are based on political geography, and in still others,
` organization names are listed directly under the country code. The
` organization for the US country domain is described in RFC 1480 [1].
`
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`MICROSOFT 1011
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`RFC 1591 Domain Name System Structure and Delegation March 1994
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` Each of the generic TLDs was created for a general category of
` organizations. The country code domains (for example, FR, NL, KR,
` US) are each organized by an administrator for that country. These
` administrators may further delegate the management of portions of the
` naming tree. These administrators are performing a public service on
` behalf of the Internet community. Descriptions of the generic
` domains and the US country domain follow.
`
` Of these generic domains, five are international in nature, and two
` are restricted to use by entities in the United States.
`
` World Wide Generic Domains:
`
` COM - This domain is intended for commercial entities, that is
` companies. This domain has grown very large and there is
` concern about the administrative load and system performance if
` the current growth pattern is continued. Consideration is
` being taken to subdivide the COM domain and only allow future
` commercial registrations in the subdomains.
`
` EDU - This domain was originally intended for all educational
` institutions. Many Universities, colleges, schools,
` educational service organizations, and educational consortia
` have registered here. More recently a decision has been taken
` to limit further registrations to 4 year colleges and
` universities. Schools and 2-year colleges will be registered
` in the country domains (see US Domain, especially K12 and CC,
` below).
`
` NET - This domain is intended to hold only the computers of network
` providers, that is the NIC and NOC computers, the
` administrative computers, and the network node computers. The
` customers of the network provider would have domain names of
` their own (not in the NET TLD).
`
` ORG - This domain is intended as the miscellaneous TLD for
` organizations that didn’t fit anywhere else. Some non-
` government organizations may fit here.
`
` INT - This domain is for organizations established by international
` treaties, or international databases.
`
` United States Only Generic Domains:
`
` GOV - This domain was originally intended for any kind of government
` office or agency. More recently a decision was taken to
` register only agencies of the US Federal government in this
` domain. State and local agencies are registered in the country
`
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`RFC 1591 Domain Name System Structure and Delegation March 1994
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` domains (see US Domain, below).
`
` MIL - This domain is used by the US military.
`
` Example country code Domain:
`
` US - As an example of a country domain, the US domain provides for
` the registration of all kinds of entities in the United States
` on the basis of political geography, that is, a hierarchy of
` <entity-name>.<locality>.<state-code>.US. For example,
` "IBM.Armonk.NY.US". In addition, branches of the US domain are
` provided within each state for schools (K12), community colleges
` (CC), technical schools (TEC), state government agencies
` (STATE), councils of governments (COG),libraries (LIB), museums
` (MUS), and several other generic types of entities (see RFC 1480
` for details [1]).
`
` To find a contact for a TLD use the "whois" program to access the
` database on the host rs.internic.net. Append "-dom" to the name of
` TLD you are interested in. For example:
`
` whois -h rs.internic.net us-dom
` or
` whois -h rs.internic.net edu-dom
`
`3. The Administration of Delegated Domains
`
` The Internet Assigned Numbers Authority (IANA) is responsible for the
` overall coordination and management of the Domain Name System (DNS),
` and especially the delegation of portions of the name space called
` top-level domains. Most of these top-level domains are two-letter
` country codes taken from the ISO standard 3166.
`
` A central Internet Registry (IR) has been selected and designated to
` handled the bulk of the day-to-day administration of the Domain Name
` System. Applications for new top-level domains (for example, country
` code domains) are handled by the IR with consultation with the IANA.
` The central IR is INTERNIC.NET. Second level domains in COM, EDU,
` ORG, NET, and GOV are registered by the Internet Registry at the
` InterNIC. The second level domains in the MIL are registered by the
` DDN registry at NIC.DDN.MIL. Second level names in INT are
` registered by the PVM at ISI.EDU.
`
` While all requests for new top-level domains must be sent to the
` Internic (at hostmaster@internic.net), the regional registries are
` often enlisted to assist in the administration of the DNS, especially
` in solving problems with a country administration. Currently, the
` RIPE NCC is the regional registry for Europe and the APNIC is the
`
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`RFC 1591 Domain Name System Structure and Delegation March 1994
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` regional registry for the Asia-Pacific region, while the INTERNIC
` administers the North America region, and all the as yet undelegated
` regions.
`
` The contact mailboxes for these regional registries are:
`
` INTERNIC hostmaster@internic.net
` APNIC hostmaster@apnic.net
` RIPE NCC ncc@ripe.net
`
` The policy concerns involved when a new top-level domain is
` established are described in the following. Also mentioned are
` concerns raised when it is necessary to change the delegation of an
` established domain from one party to another.
`
` A new top-level domain is usually created and its management
` delegated to a "designated manager" all at once.
`
` Most of these same concerns are relevant when a sub-domain is
` delegated and in general the principles described here apply
` recursively to all delegations of the Internet DNS name space.
`
` The major concern in selecting a designated manager for a domain is
` that it be able to carry out the necessary responsibilities, and have
` the ability to do a equitable, just, honest, and competent job.
`
` 1) The key requirement is that for each domain there be a designated
` manager for supervising that domain’s name space. In the case of
` top-level domains that are country codes this means that there is
` a manager that supervises the domain names and operates the domain
` name system in that country.
`
` The manager must, of course, be on the Internet. There must be
` Internet Protocol (IP) connectivity to the nameservers and email
` connectivity to the management and staff of the manager.
`
` There must be an administrative contact and a technical contact
` for each domain. For top-level domains that are country codes at
` least the administrative contact must reside in the country
` involved.
`
` 2) These designated authorities are trustees for the delegated
` domain, and have a duty to serve the community.
`
` The designated manager is the trustee of the top-level domain for
` both the nation, in the case of a country code, and the global
` Internet community.
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`RFC 1591 Domain Name System Structure and Delegation March 1994
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` Concerns about "rights" and "ownership" of domains are
` inappropriate. It is appropriate to be concerned about
` "responsibilities" and "service" to the community.
`
` 3) The designated manager must be equitable to all groups in the
` domain that request domain names.
`
` This means that the same rules are applied to all requests, all
` requests must be processed in a non-discriminatory fashion, and
` academic and commercial (and other) users are treated on an equal
` basis. No bias shall be shown regarding requests that may come
` from customers of some other business related to the manager --
` e.g., no preferential service for customers of a particular data
` network provider. There can be no requirement that a particular
` mail system (or other application), protocol, or product be used.
`
` There are no requirements on subdomains of top-level domains
` beyond the requirements on higher-level domains themselves. That
` is, the requirements in this memo are applied recursively. In
` particular, all subdomains shall be allowed to operate their own
` domain name servers, providing in them whatever information the
` subdomain manager sees fit (as long as it is true and correct).
`
` 4) Significantly interested parties in the domain should agree that
` the designated manager is the appropriate party.
`
` The IANA tries to have any contending parties reach agreement
` among themselves, and generally takes no action to change things
` unless all the contending parties agree; only in cases where the
` designated manager has substantially mis-behaved would the IANA
` step in.
`
` However, it is also appropriate for interested parties to have
` some voice in selecting the designated manager.
`
` There are two cases where the IANA and the central IR may
` establish a new top-level domain and delegate only a portion of
` it: (1) there are contending parties that cannot agree, or (2) the
` applying party may not be able to represent or serve the whole
` country. The later case sometimes arises when a party outside a
` country is trying to be helpful in getting networking started in a
` country -- this is sometimes called a "proxy" DNS service.
`
` The Internet DNS Names Review Board (IDNB), a committee
` established by the IANA, will act as a review panel for cases in
` which the parties can not reach agreement among themselves. The
` IDNB’s decisions will be binding.
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`RFC 1591 Domain Name System Structure and Delegation March 1994
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` 5) The designated manager must do a satisfactory job of operating the
` DNS service for the domain.
`
` That is, the actual management of the assigning of domain names,
` delegating subdomains and operating nameservers must be done with
` technical competence. This includes keeping the central IR (in
` the case of top-level domains) or other higher-level domain
` manager advised of the status of the domain, responding to
` requests in a timely manner, and operating the database with
` accuracy, robustness, and resilience.
`
` There must be a primary and a secondary nameserver that have IP
` connectivity to the Internet and can be easily checked for
` operational status and database accuracy by the IR and the IANA.
`
` In cases when there are persistent problems with the proper
` operation of a domain, the delegation may be revoked, and possibly
` delegated to another designated manager.
`
` 6) For any transfer of the designated manager trusteeship from one
` organization to another, the higher-level domain manager (the IANA
` in the case of top-level domains) must receive communications from
` both the old organization and the new organization that assure the
` IANA that the transfer in mutually agreed, and that the new
` organization understands its responsibilities.
`
` It is also very helpful for the IANA to receive communications
` from other parties that may be concerned or affected by the
` transfer.
`
`4. Rights to Names
`
` 1) Names and Trademarks
`
` In case of a dispute between domain name registrants as to the
` rights to a particular name, the registration authority shall have
` no role or responsibility other than to provide the contact
` information to both parties.
`
` The registration of a domain name does not have any Trademark
` status. It is up to the requestor to be sure he is not violating
` anyone else’s Trademark.
`
` 2) Country Codes
`
` The IANA is not in the business of deciding what is and what is
` not a country.
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`RFC 1591 Domain Name System Structure and Delegation March 1994
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` The selection of the ISO 3166 list as a basis for country code
` top-level domain names was made with the knowledge that ISO has a
` procedure for determining which entities should be and should not
` be on that list.
`
`5. Security Considerations
`
` Security issues are not discussed in this memo.
`
`6. Acknowledgements
`
` Many people have made comments on draft version of these descriptions
` and procedures. Steve Goldstein and John Klensin have been
` particularly helpful.
`
`7. Author’s Address
`
` Jon Postel
` USC/Information Sciences Institute
` 4676 Admiralty Way
` Marina del Rey, CA 90292
`
` Phone: 310-822-1511
` Fax: 310-823-6714
` EMail: Postel@ISI.EDU
`
`7. References
`
` [1] Cooper, A., and J. Postel, "The US Domain", RFC 1480,
` USC/Information Sciences Institute, June 1993.
`
` [2] Reynolds, J., and J. Postel, "Assigned Numbers", STD 2, RFC 1340,
` USC/Information Sciences Institute, July 1992.
`
` [3] Mockapetris, P., "Domain Names - Concepts and Facilities", STD
` 13, RFC 1034, USC/Information Sciences Institute, November 1987.
`
` [4] Mockapetris, P., "Domain Names - Implementation and
` Specification", STD 13, RFC 1035, USC/Information Sciences
` Institute, November 1987.
`
` [6] Partridge, C., "Mail Routing and the Domain System", STD 14, RFC
`974, CSNET CIC BBN, January 1986.
`
` [7] Braden, R., Editor, "Requirements for Internet Hosts --
` Application and Support", STD 3, RFC 1123, Internet Engineering
` Task Force, October 1989.
`
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