International call

International telephone calls are those made between different countries. These telephone calls are processed by international gateway exchanges (switches). Charges for these calls were high initially but declined greatly during the 20th century due to advances in technology and liberalization. Originally they were placed via long-distance operators. The calls were transmitted by cable, communications satellite, radio, and more recently, fiber optics and Voice over Internet Protocol (VoIP). International Direct Dialling was introduced in the 1970s, so calls can be dialed by country code without an operator.

International calls can be paid via telephone card (aka phone card, calling card). These popular telecommunications products allow users to initiate an international call from almost anywhere in the world. These cards typically offer rates lower than most traditional long distance products and services, and can be used via landline, cellular phone, PBX, and some VoIP services, as well as from some airports and hotels.

In the United Kingdom, there are various ways to make an international call.[1] For users with access to a landline:

For mobile phone users, the choices used to be very limited but it is no longer the case as mobile phone network operators roll out new pricing models and innovation in call routing developed. There are now numerous ways for a mobile phone user to call internationally:

A Local Dialling Disparity exists where the originating number and the foreign number are on the same network, usually a mobile telephone provider with operations in multiple countries. A less expensive call path is available by routing within the local Mobile Switching Center without going out to the global GMSC to its HLR. Both users are on the same network, so the international call remains within that company's network.

There are instances of telephone country codes covering points in more than one country; the North American Numbering Plan is one example, as is nominally-sovereign Vatican City's use of Italian numbering. The term overseas call is used by the Bell System to distinguish international calls to another country code from NANP-internal calls.

See also

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This article is issued from Wikipedia - version of the 3/22/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.