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:
“The home is a womans natural background.... From the beginning I tried to have the policy of the store reflect as nearly as it was possible in the commercial world, those standards of comfort and grace which are apparent in a lovely home.”
—Hortense Odlum (1892?)
“The technologist was the final guise of the white missionary, industrialization the last gospel of a dying race and living standards a substitute for a purpose in living.”
—Max Frisch (19111991)
“A generation which has passed through the shop has absorbed standards and ambitions which are not of those of spaciousness, and cannot get away from them. Everything with them is done as though for sale, and they naturally have in view the greatest possible benefit, profit and that end of the stuff that will make the best show.”
—Alexander Herzen (18121870)