As per Relevance of the word structure, we have this rfc below:
Network Working Group G. Huston,
Request for Comments: 3172
BCP: 52 September 2001
Category: Best Current
Management Guidelines & Operational Requirements
the Address and Routing Parameter Area Domain ("arpa")
Status of this
This document specifies an Internet Best Current Practices for
Internet Community, and requests discussion and suggestions
improvements. Distribution of this memo is unlimited
Copyright
Copyright (C) The Internet Society (2001). All Rights Reserved
This memo describes the management and operational requirements
the address and routing parameter area ("arpa") domain. The "arpa
domain is used to support a class of infrastructural
spaces, providing a distributed database that translates elements
a structured name space derived from a protocol family to
names. The efficient and reliable operation of this DNS space
essential to the integrity of operation of various services
the Internet. The Internet Architecture Board (IAB) has
responsibility, in cooperation with the Internet Corporation
Assigned Names and Numbers (ICANN), to manage the "arpa" domain
This document describes the principles used by the IAB in
this role
1.
The Domain Name System (DNS) [1] [2] is predominately used
translate a structured textual identifier into a protocol-
value. It uses the structure embedded within a
identifier space to create a distributed database, where every
within the database corresponds to a node within the name structure
The most prevalent role of the DNS is to store a set of name
address translations, allowing a domain name to be translated to
IP address. The DNS is also used to store a number of
translations from hierarchically structured identifier spaces
target values of various types
Huston Best Current Practice [Page 1]
RFC 3172 arpa Guidelines September 2001
The DNS is also capable of supporting a translation in the
direction, from protocol values to the names of service entities
One approach in using the DNS in this fashion has been to
protocol values into a hierarchically structured identifier space
and then use these transformed protocol value names as a DNS
key into the appropriate DNS name hierarchy. A common use of
mechanism has been the reverse of the name to address lookup
allowing for an IPv4 address to be used to look up a matching
name. For example, the IP address 128.9.160.55 can be
with the domain name "www.iab.org." by creating the DNS
55.160.9.128.in-addr.arpa." and mapping this entry, via a DNS
record, to the value "www.iab.org.".
The resolution of protocol objects into service names is used by
number of applications to associate services with a
protocol object. The correct and efficient operation of
applications is dependent on the correct and efficient operation
the associated "arpa" domain name servers
2. The "arpa"
The "arpa" domain was originally established as part of the
deployment of the DNS, to provide a transition mechanism from
Host Tables that were common in the ARPANET, as well as a home
the IPv4 reverse mapping domain. During 2000, the abbreviation
redesignated to "Address and Routing Parameter Area" in the hope
reducing confusion with the earlier network name
The Internet Architecture Board (IAB), in cooperation with
Internet Corporation for Assigned Names and Numbers (ICANN),
currently responsible for managing the Top Level Domain (TLD)
"arpa". This arrangement is documented in Appendix A. This
name provides the root of the name hierarchy of the reverse
of IP addresses to domain names. More generally, this domain
undertakes a role as a limited use domain for
infrastructure applications, by providing a name root for the
of particular protocol values to names of service entities.
domain name provides a name root for the mapping of protocol
into lookup keys to retrieve operationally critical
infrastructure data records or objects for the Internet
The IAB may add other infrastructure uses to the "arpa" domain in
future. Any such additions or changes will be in accordance with
procedures documented in Section 2.1 and Section 3 of this document
Huston Best Current Practice [Page 2]
RFC 3172 arpa Guidelines September 2001
This domain is termed an "infrastructure domain", as its role is
support the operating infrastructure of the Internet. In particular
the "arpa" domain is not to be used in the same manner (e.g.,
naming hosts) as other generic Top Level Domains are commonly used
The operational administration of this domain, in accordance with
provisions described in this document, shall be performed by the
under the terms of the MoU between the IAB and ICANN concerning
IANA [3].
2.1 Criteria for "arpa" Sub-
The "arpa" sub-domains are used for those protocol object
defined as part of the Internet Standards Process [4], and
recommended to be managed as infrastructure protocol objects
Normally, the recommendation is to be made in the "
Considerations" section of the Internet Standard
specification. The recommendation should include the manner in
protocol objects are to be mapped into lookup keys,
recommendations to IANA concerning the operation of the "arpa" sub
domain in conjunction with the recommendations concerning
operation of the protocol object registry itself
The IESG consideration of a document which proposes the use of
"arpa" sub-domain shall include consideration of the "
Considerations" section. If the document is approved, the IESG
ask the IAB to request the IANA to add the corresponding
object sub-domain domain to the "arpa" domain, in accordance with
2860 [3], with administration of the sub-domain undertaken
accordance with the provisions described in this document
2.2 "arpa" Name Server
As this domain is part of the operationally critical
of the Internet, the stability, integrity and efficiency of
operation of this domain is a matter of importance for all
users
The "arpa" domain is positioned as a top level domain in order
avoid potential operational instabilities caused by multiple
lookups spanning several operational domains that would be
to locate the servers of each of the parent names of a more
nested infrastructure name. The maximal lookup set for "arpa" is
lookup of the name servers for the "arpa" domain from a root server
and the query agent is then provided with a list of
"arpa" name servers
Huston Best Current Practice [Page 3]
RFC 3172 arpa Guidelines September 2001
The efficient and correct operation of the "arpa" domain
considered to be sufficiently critical that the
requirements for the root servers apply to the
requirements of the "arpa" servers. All operational
noted in RFC 2870 [5] as they apply to the operational
of the root servers shall apply to the operation of the "arpa
servers. Any revision to RFC 2870 in relation to the operation
the root servers shall also apply to the operation of the "arpa
servers
Many of the servers that are authoritative for the root zone (or
"." zone) also currently serve as authoritative for the "arpa" zone
As noted in RFC 2870 [5], this arrangement is likely to change in
future
3. Delegation of "arpa" Sub-
While the decision as to which protocol elements are loaded into
"arpa" domain, and the hierarchical structure of such
elements, remains within the role of the IAB, the role of
the sub-domain may be delegated by the IAB to an appropriate
management entity
The IAB shall only recommend the creation of "arpa" sub-
corresponding to protocol entities where
- the delegation, and the hierarchical name structure, is
by an IETF Standards Track document [4],
- the use of the "arpa" domain is explicitly recommended in
"IANA Considerations" section of that document
The "IANA Considerations" section should include the name of
subdomain, the rules for how the subdomain is to be administered,
the criteria for entries within the subdomain
4. Current Status of "arpa
The "arpa" domain is used for the sub-domains "in-addr.arpa" [1],
"ip6.arpa" [7] and "e164.arpa" [8].
Currently, the "arpa" zone is located on a subset of the
servers, and the zone is managed in accordance with
specifications. The IAB is working with ICANN, IANA, and
regional registries to move "arpa" and "in-addr.arpa" records
the root servers in accord with the RFC 2870 recommendation
exclusive use of those servers [5].
Huston Best Current Practice [Page 4]
RFC 3172 arpa Guidelines September 2001
The IPv4 reverse address domain, "in-addr.arpa" is delegated to
IANA. The "in-addr.arpa" zone is currently located on the same
subset of the root servers as "arpa". Sub-delegations within
hierarchy are undertaken in accordance with the IANA's
allocation practices
The "ip6.arpa" IPv6 reverse address domain uses a method
delegation that is the same as is used for "in-addr.arpa", where
"ip6.arpa" domain is delegated to the IANA, and names within
zone further delegated to the regional IP registries in
with the delegation of IPv6 address space to those registries [6]
[7].
The "e164.arpa" domain is used to map E.164 style phone numbers
URIs. This mechanism is defined in RFC 2916 [9]. RFC 2916
that the provision that names within this DNS zone are to
delegated to parties according to ITU recommendation E.164 [10].
3026 [8] describes the overall liaison arrangements between the
and ITU-T about the use of this domain
5. Infrastructure domains elsewhere in the DNS
Any infrastructure domains that are located elsewhere in the DNS
than as sub-domains of "arpa", for historical or other reasons
should adhere to all of the requirements established in this
for sub-domains of "arpa", and consideration should be given
migrating them into "arpa" as and when appropriate
6. Security
The security considerations as documented in RFC 2870 [5], and
successors to that document, apply to the operation of the "arpa
servers
The security considerations specific to the E.164 subdomain
documented in Section 5 of RFC 2916 [9].
Any new subdomain delegation must adequately document any
considerations specific to the information stored therein
7. IANA
As noted in section 3 of this document, the IAB may request the
to delegate the sub-domains of "arpa" in accordance with the "
Considerations" section of an IETF Standards Track document.
request falls under the scope of section 4 of the MoU between
IETF and ICANN concerning the IANA [3].
Huston Best Current Practice [Page 5]
RFC 3172 arpa Guidelines September 2001
This document is a document of the IAB, and the editor
the contributions of the members of the IAB in the preparation of
document. In addition, suggestions have been incorporated from
Bradner
[1] Mockapetris, P., "Domain names - concepts and facilities",
13, RFC 1034, November 1987.
[2] Mockapetris, P., "Domain names - implementation
specification", STD 13, RFC 1035, November 1987.
[3] Carpenter, B., Baker, F. and M. Roberts, "Memorandum
Understanding Concerning the Technical Work of the
Assigned Numbers Authority", RFC 2860, June 2000.
[4] Bradner, S., "The Internet Standards Process -- Revision 3",
9, RFC2026, October 1996.
[5] Bush, R., Karrenberg, D., Kosters, M. and R. Plzak, "Root
Server Operational Requirements", BCP 40, RFC 2870, June 2000.
[6] Crawford, M. and C. Huitema, "DNS Extensions to Support IPv
Address Aggregation and Renumbering", RFC 2874, July 2000.
[7] Bush, R., "Delegation of IP6.arpa", BCP 49, RFC 3152,
2001.
[8] Blane, P., "Liaison to IETF/ISOC on ENUM", RFC 3026,
2001.
[9] Falstrom, P., "E.164 number and DNS", RFC 2916, September 2000.
[10] ITU-T Recommendation E.164/I.331 (05/97): The
Public Telecommunication Numbering Plan. 1997.
Author's
Internet Architecture
Geoff Huston,
iab@iab.
Huston Best Current Practice [Page 6]
RFC 3172 arpa Guidelines September 2001
Appendix
April 28, 2000
Mr. Louis
Vice-President, Secretary, and General
Internet Corporation for Assigned Names and
4676 Admiralty Way, Suite 330
Marina del Rey, CA 90292
Re: Purchase Order No. 40SBNT067020:
Administration of the arpa Top Level
Dear Mr. Touton
As noted in your organization's quotation of February 2, 2000,
arpa Top Level Domain (TLD) exists in the root zone of the
name system as a limited use domain currently consisting of
record, in-addr.arpa. On April 14, 2000, the Defense
Research Projects Agency (DARPA), formerly known as the
Research Projects Agency (ARPA), officially signaled
disassociation with the arpa domain and its understanding the
would be used by the Internet Corporation for Assigned Names (ICANN
and Numbers and the Internet Architecture Board (IAB) for
Internet infrastructure uses
In keeping with the DARPA understanding, we believe that the
domain should be made available for this specific, limited purpose
The Department of Commerce considers this an Internet
Numbers Authority (IANA) function and has requested that the
entry for the arpa domain reflect IANA as the registrant
Purchase Order No. 40SBNT067020 provides that "[ICANN] will
other IANA functions as needed upon request of DOC." As such,
Department of Commerce requests that, as part of the IANA functions
ICANN undertake administration of the arpa TLD in cooperation
the Internet technical community under the guidance of the IAB, as
limited use domain for Internet infrastructure applications
including the migration of Internet infrastructure applications
currently reside in the .int TLD. Further, as indicated by DARPA
the arpa TLD string should be given a different expansion such
"Address and Routing Parameter Area" to avoid any implication
DARPA has operational responsibility for the domain
If you have any questions, please do not hesitate to contact me
Sincerely, Karen
Purchase Order Technical
Huston Best Current Practice [Page 7]
RFC 3172 arpa Guidelines September 2001
Full Copyright
Copyright (C) The Internet Society (2001). All Rights Reserved
This document and translations of it may be copied and furnished
others, and derivative works that comment on or otherwise explain
or assist in its implementation may be prepared, copied,
and distributed, in whole or in part, without restriction of
kind, provided that the above copyright notice and this paragraph
included on all such copies and derivative works. However,
document itself may not be modified in any way, such as by
the copyright notice or references to the Internet Society or
Internet organizations, except as needed for the purpose
developing Internet standards in which case the procedures
copyrights defined in the Internet Standards process must
followed, or as required to translate it into languages other
English
The limited permissions granted above are perpetual and will not
revoked by the Internet Society or its successors or assigns
This document and the information contained herein is provided on
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED,
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
Funding for the RFC Editor function is currently provided by
Internet Society
Huston Best Current Practice [Page 8]
if you see any problems within the linking, don't worry be happy,
this is version 0.1 of the Relevance System and you gotta expect some crappy subroutines sometimes,
just be content we did not write this in Java, which would have made this "bigger and better" HAHAHHA.
RFC documents can be found at I.E.T.F.
Relevance System Copyright © 2002 Spectrum WorldResearch
other technical nosh by ServerMasters Corporation
collaboration of BobX
