Domain Name System Structure and Delegation (RFC1591)
Original Publication Date: 1994-Mar-01
Included in the Prior Art Database: 2019-Feb-13
Internet Society Requests For Comment (RFCs)
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. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.
Network Working Group J. Postel 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.
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 .
Postel [Page 1]
RFC 1591 Domain Name System Structure and Delegation March 1994
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 registra...