E.164 is an ITU-T recommendation which defines the international public telecommunication numbering plan used in the PSTN and some other data networks. It also defines the format of telephone numbers. E.164 numbers can have a maximum of 15 digits and are usually written with a + prefix. To actually dial such numbers from a normal fixed line phone the appropriate international call prefix must be used. The ITU Telecommunication Standardization Sector (ITU-T) coordinates standards for telecommunications on behalf of the International Telecommunication Union (ITU) and is based in Geneva, Switzerland. ... Telecommunication involves the transmission of signals over a distance for the purpose of communication. ... A numbering plan is a type of numbering scheme used in telecommunications. ... The public switched telephone network (PSTN) is the concatenation of the worlds public circuit-switched telephone networks, in much the same way that the Internet is the concatenation of the worlds public IP-based packet-switched networks. ... A telecommunications network is a network of telecommunications links arranged so that messages may be passed from one part of the network to another over multiple links. ... A telephone number is a sequence of decimal digits that uniquely indicates the network termination point. ... Each country has both a country calling code used to dial into a country, and an international call prefix or international access code used to dial out of the country. ...

The title of the original and revision 1 was "Numbering Plan for the ISDN era". ISDN redirects here. ...

Categories

This recommendation provides the number structure and functionality for the three categories of numbers used for international public telecommunication: Copy of the original phone of Alexander Graham Bell at the Musée des Arts et Métiers in Paris Telecommunication is the transmission of signals over a distance for the purpose of communication. ...

For each of the categories, it details the components of the numbering structure and the digit analysis required to successfully route the calls. Annex A provides additional information on the structure and function of E.164 numbers. Annex B provides information on network identification, service parameters, calling/connected line identity, dialling procedures, and addressing for Geographic-based ISDN calls. Specific E.164 based applications which differ in usage are defined in separate recommendations. This article is about routing (or routeing) in computer networks. ... The factual accuracy of this article is disputed. ... A procedure is a series of activities, tasks, steps, decisions, calculations and other processes, that when undertaken in the sequence laid down produces the described result, product or outcome. ... Physical map of the Earth (Medium) (Large 2 MB) Geography is the scientific study of the locational and spatial variation in both physical and human phenomena on Earth. ... ISDN is also short for isosorbide dinitrate Integrated Services Digital Network (ISDN) is a type of circuit switched telephone network system, designed to allow digital (as opposed to analog) transmission of voice and data over ordinary telephone copper wires, resulting in better quality and higher speeds, than available with analog...

The number categories are all based on a 15-digit numbering space (excluding prefixes; before 1997, only 12 digits were allowed). They are as follows:

Number structure for geographic area

Number structure for global services

Number structure for networks

Number structure for groups of countries

Recommendations contained in E.164

E.164.1

This recommendation describes the procedures and criteria for the reservation, assignment, and reclamation of E.164 country codes and associated Identification Code (IC) assignments. The criteria and procedures are provided as a basis for the effective and efficient utilization of the available E.164 numbering resources. Such assignments require a collaborative effort between the ITU-TSB and the appropriate ITU-T Study Group to endeavor to ensure that the assignments meet the needs of the telecommunication community. The development of these criteria and procedures are in accordance with the principles contained in E.190 and the numbering plan formats detailed in E.164. Criterion DVD Series The Criterion Collection, a continuing series of important classic and contemporary films, is dedicated to gathering the greatest films from around the world and publishing them in editions that offer the highest technical quality and award-winning, original supplements. ... In computer programming, an assignment is the defining of a variable. ... Land reclamation is either of two distinct practices. ... Collaboration, literally, consists of working together with one or more others. ...

E.164.2

This recommendation contains the criteria and procedures for an applicant to be temporarily assigned a three-digit identification code within the shared E.164 country code 991 for the purpose of conducting an international non-commercial trial.

E.164.3

This recommendation describes the principles, criteria, and procedures for the assignment and reclamation of resources within a shared E.164 Country Code for groups of countries. These shared Country Codes will coexist with all other E.164-based Country Codes assigned by the ITU. The resource of the shared Country Code consists of a Country Code and a Group Identification Code (CC + GIC) and provides the capability for a Group of Countries to provide telecommunication services within the Group of countries. The TSB is responsible for the assignment of the CC + GIC.

Addresses

E.164 addresses can be used in DNS by using Telephone Number Mapping (ENUM) which allocates a specific zone, primarily e164.arpa for use with E.164 numbers. Any phone number, such as +1 555 42 42 can be transformed into a hostname by reversing the numbers, separating them with dots and adding the e164.arpa suffix, like so: It has been suggested that this article be split into multiple articles. ... Telephone Number Mapping (ENUM or Enum, from TElephone NUmber Mapping) is a suite of protocols to unify the telephone system with the Internet by using E.164 addresses with DDDS and DNS. ENUM also refers to E164 NUmber Mapping. Although it facilitates VoIP, the protocol used for voice communication across... A hostname (occasionally also, a sitename) is the unique name by which a network attached device (which could consist of a computer, file server, network storage device, fax machine, copier, cable modem, etc. ...

2.4.2.4.5.5.5.1.e164.arpa

(There is a related "experiment in remote printing" using the tpc.int domain, that uses this method to address email to fax machines.)

DNS can then be used to look up Internet addresses for services such as SIP VoIP telephony. An alternate method is DUNDi, which is a P2P implementation of ENUM^[1]. DUNDi is yet to be standarised by the IETF. The Session Initiation Protocol (SIP) is an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants. ... IP Telephony, also called Internet telephony, is the technology that makes it possible to have a telephone conversation over the Internet or a dedicated Internet Protocol (IP) network instead of dedicated voice transmission lines. ... Wikipedia does not have an article with this exact name. ... A peer-to-peer (or P2P) computer network is a network that relies on the computing power and bandwidth of the participants in the network rather than concentrating it in a relatively few servers. ... -1... The Internet Engineering Task Force (IETF) is charged with developing and promoting Internet standards. ...

E.163 was the old ITU-T standard for describing telephone numbers for the public switched telephone network (PSTN). In the United States this was formerly referred to as a directory number. E.163 was deleted and incorporated into revision 1 of E.164 in 1997. E.163 was an ITU-T standard for describing telephone numbers for the public voice network (PSTN). ... The ITU Telecommunication Standardization Sector (ITU-T) coordinates standards for telecommunications on behalf of the International Telecommunication Union (ITU) and is based in Geneva, Switzerland. ... For other uses, see Telephone (disambiguation). ... The public switched telephone network (PSTN) is the network of the worlds public circuit-switched telephone networks, in much the same way that the Internet is the network of the worlds public IP-based packet-switched networks. ...

See also

• List of country calling codes
• DUNDi
• ENUM

This is a list of country calling codes defined by ITU-T recommendation E.164. ... Distributed Universal Number Discovery (DUNDi) is a P2P protocol for providing services equivalent to those provided by ENUM. DUNDi has an advantage above ENUM in that is far more resilient, as it lacks a central point of failure. ... -1...

External links

• http://www.itu.int
• Downloadable List of International Calling Codes

References

1. ^ DUNDi.