Telephone Numbering Plan - Standards

Standards

Although the International Telecommunication Union (ITU) has attempted to promote common standards among nation states, numbering plans take different formats in different parts of the world. For example, the ITU recommends that member states adopt 00 as their international access code. However, as these recommendations are not binding on member states, some have not, such as the United States, Canada, and other countries and territories participating in the North American Numbering Plan.

The international numbering plan establishes country codes, that is, area codes that denote nations or groups of nations. The E.164 standard regulates country codes at the international level and sets a maximum length limit on a full international phone number (15 digits). However, it is each country's responsibility to define the numbering within its own network. As a result, regional area codes may be:

  • A fixed length, e.g., three digits in the United States and Canada; two digits in Brazil; one digit in Australia and New Zealand,
  • A variable length, e.g., between 2 and 5 in Germany, Argentina, United Kingdom and in Austria; between 1 and 5 in Japan; 1 or 2 in Syria and Peru, or
  • Incorporated into the subscriber's number, as is the case in many countries, such as Spain or Norway. This is known as a "closed" telephone numbering plan. In some cases a trunk code (usually 0) must still be dialed, as in Belgium, Italy, Switzerland, South Africa and some locations within the NANP. Hong Kong used to have 1-digit area codes. They were incorporated into the subscriber's numbers back into the 1990s. No trunk code is required.

Read more about this topic:  Telephone Numbering Plan

Famous quotes containing the word standards:

    Chief among our gains must be reckoned this possibility of choice, the recognition of many possible ways of life, where other civilizations have recognized only one. Where other civilizations give a satisfactory outlet to only one temperamental type, be he mystic or soldier, business man or artist, a civilization in which there are many standards offers a possibility of satisfactory adjustment to individuals of many different temperamental types, of diverse gifts and varying interests.
    Margaret Mead (1901–1978)

    With his brows knit, his mind made up, his will resolved and resistless, he advances, crashing his way through the host of weak, half-formed, dilettante opinions, honest and dishonest ways of thinking, with their standards raised, sentimentalities and conjectures, and tramples them all into dust. See how he prevails; you don’t even hear the groans of the wounded and dying.
    Henry David Thoreau (1817–1862)

    Barbarism is the absence of standards to which appeal can be made.
    José Ortega Y Gasset (1883–1955)