Common Language Location Identification
identifier used in the telecommunications industry in North America
Common Language Location Identification (CLLI) is an application of Common Language Information Services in the North American telecommunications industry. It specifies the location and function of telecommunication equipment or of a relevant location such as an international border or a supporting equipment location, such as a manhole or pole. CLLI was developed in the 1960s in the Bell System, and continued use after divestiture in the North American market under management by Bellcore, later renamed to Telcordia and Iconectiv, which claims trademarks on the names "Common Language" and "CLLI".
CLLI codes are useful to telecommunications companies for ordering telephone service, for the rating of call detail records for billing purposes, and to assist in tracing calls. CLLI codes are associated with Vertical and Horizontal coordinates (frequently abbreviated to "V and H coordinates"), which were developed by AT&T researcher Jay K. Donald to provide a relatively simple method of calculating distance between two network locations. Various mileage-sensitive services are priced according to the V and H coordinates associated with the two endpoints' CLLI codes.
Structure
The first six characters of a CLLI code represent the place the code refers to and contain two code elements:
Four characters to denote the geographical area and the geographical area type (for example, city, town, and borough), known as the Geographical code element.
Two characters to denote the state, province, or country, known as the Geopolitical code element. The codes HS (high seas) and EO (earth orbit) are reserved for ships at sea and satellites, respectively.
For the various code formats, the remaining two or five characters contain one of:
A two-character building identifier, either two letters or two numbers, for telephone company buildings.
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This entry incorporates text from “Common Language Location Identification” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.