Local access and transport area

It represents a geographical area of the United States under the terms of the Modification of Final Judgment (MFJ) entered by the United States District Court for the District of Columbia in Civil Action number 82-0192 or any other geographic area designated as a LATA in the National Exchange Carrier Association, Inc.

Under the terms of the MFJ, the RBOCs are generally prohibited from providing services that originate in one LATA and terminate in another.

LATA boundaries tend to be drawn around markets, and not necessarily along existing state or area code borders.

Since the breakup of the Bell System in 1984, however, some amount of deregulation, as well as a number of phone company mergers, have blurred the significance of these regions.

Inter-carrier agreements, change proposals to the Federal Communications Commission (FCC), and new wiring developments into rural areas can and do often alter the effective borders between LATAs.

As LATAs exist for US regulatory purposes, where they serve as a demarcation between intra-LATA calls (handled by regional Bell operating companies) and inter-LATA calls (handled by interstate long-distance carriers such as AT&T), they have no legal significance in Canada.

[4] A Canadian LIR is geographically smaller than a US LATA, typically comparable in size to a small city's flat-rate local calling area or to an entire large regional municipality.

While the LIRs resemble local calling areas in geographic size, there are some key differences: One example: The tiny unincorporated village of Beebe Plain, divided by the Quebec-Vermont border, is served by +1-819-876 Rock Island, Quebec, Canada (a remote station controlled from Magog) and +1-802-873 Derby Line, Vermont, USA (a remote station controlled from St. Johnsbury).