E.164
Encyclopedia
E.164 is an ITU-T
recommendation that defines the international public telecommunication numbering plan used in the PSTN and some other data networks
. It also defines the format of telephone number
s. E.164 numbers can have a maximum of fifteen 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 title of the original and revision 1 was "Numbering Plan for the ISDN
Era".
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, dialing procedures, and addressing for Geographic-based ISDN calls. Specific E.164-based applications which differ in usage are defined in separate recommendations.
The number categories are all based on a fifteen-digit numbering space (excluding prefixes; before 1997, only twelve digits were allowed). They are as follows:
, 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.
recommendation 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 E.163 was withdrawn, and some recommendations were incorporated into revision 1 of E.164 in 1997.
ITU-T
The ITU Telecommunication Standardization Sector is one of the three sectors of the International Telecommunication Union ; it coordinates standards for telecommunications....
recommendation that defines the international public telecommunication numbering plan used in the PSTN and some other data networks
Telecommunications network
A telecommunications network is a collection of terminals, links and nodes which connect together to enable telecommunication between users of the terminals. Networks may use circuit switching or message switching. Each terminal in the network must have a unique address so messages or connections...
. It also defines the format of telephone number
Telephone number
A telephone number or phone number is a sequence of digits used to call from one telephone line to another in a public switched telephone network. When telephone numbers were invented, they were short — as few as one, two or three digits — and were given orally to a switchboard operator...
s. E.164 numbers can have a maximum of fifteen 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 title of the original and revision 1 was "Numbering Plan for the ISDN
Integrated Services Digital Network
Integrated Services Digital Network is a set of communications standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network...
Era".
Categories
This recommendation provides the number structure and functionality for the three categories of numbers used for international public telecommunication:For each of the categories, it details the components of the numbering structure and the digit analysis required to successfully route
Routing
Routing is the process of selecting paths in a network along which to send network traffic. Routing is performed for many kinds of networks, including the telephone network , electronic data networks , and transportation networks...
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, dialing procedures, and addressing for Geographic-based ISDN calls. Specific E.164-based applications which differ in usage are defined in separate recommendations.
The number categories are all based on a fifteen-digit numbering space (excluding prefixes; before 1997, only twelve digits were allowed). They are as follows:
Number structure for geographic area
| Country Code | National Destination Code (optional) | Subscriber Number |
|---|---|---|
| National (significant) number | ||
| cc = 1 to 3 digits | maximum = 15 − cc digits | |
| International public telecommunication number for geographic areas (maximum 15 digits) | ||
- D0160
Number structure for global services
| Country Code | Global Subscriber Number |
|---|---|
| cc = 3 digits | maximum = 15 − cc digits |
| International public telecommunication number for global services (maximum 15 digits) | |
Number structure for networks
| Country Code | Identification Code | Subscriber Number |
|---|---|---|
| cc = 3 digits | x = 1 to 4 digits | maximum = 15 − (cc + x) digits |
| International public telecommunication number for networks (maximum 15 digits) | ||
Number structure for groups of countries
| Country Code | Group Identification Code | Subscriber Number |
|---|---|---|
| cc = 3 digits | gic = 1 digit | maximum = 15 − (cc + gic) = 11 digits |
| International public telecommunication number for groups of countries (maximum 15 digits) | ||
E.164.1
This recommendation describes the procedures and criteria for the reservation, assignmentAssignment
'Assignment may refer to:* Assignment , a type of modification to a variable* Assignment , a task given to students by their teachers to be completed out of the class time....
, 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
Collaboration
Collaboration is working together to achieve a goal. It is a recursive process where two or more people or organizations work together to realize shared goals, — for example, an intriguing endeavor that is creative in nature—by sharing...
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.
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. The TSB is responsible for the assignment of the CC + GIC.E.163
E.163 was the former ITU-TITU-T
The ITU Telecommunication Standardization Sector is one of the three sectors of the International Telecommunication Union ; it coordinates standards for telecommunications....
recommendation for describing telephone
Telephone
The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...
numbers for the public switched telephone network
Public switched telephone network
The public switched telephone network is the network of the world's public circuit-switched telephone networks. It consists of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all inter-connected by...
(PSTN). In the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, this was formerly referred to as a directory number. E.163 was withdrawn, and some recommendations were incorporated into revision 1 of E.164 in 1997.