I've got your number

 

I’ve got your number means understanding someone so well that you can predict their actions or know someone’s true nature or intentions. It’s an idiom—a phrase whose meaning isn’t deduced from the literal definitions of the words it contains.

This phrase came to mind the other day when I got a call from someone that I did not know in Aurora, Illinois. The odd thing is that the area code was 331, an area code that did not exist when we lived there. The new area code is actually an overlap to the existing area code of 630, and it became effective in 2007, about 3 years after we moved out of the area.

 The encounter with a new area code got me to wondering about the origins of area codes.

First of all, I dug into the origin of the North American Numbering Plan.

The North American Numbering Plan (NANP) divides the territories of its members into geographic numbering plan areas (NPAs). Each NPA is identified by one or more numbering plan area codes (NPA codes, or area codes), consisting of three digits that are prefixed to each local telephone number having seven digits. A numbering plan area with multiple area codes is called an overlay. Area codes are also assigned for non-geographic purposes. The rules for numbering NPAs do not permit the digits 0 and 1 in the leading position. Area codes with two identical trailing digits are easily recognizable codes (ERC). NPAs with 9 in the second position are reserved for future format expansion.

The North American Numbering Plan (NANP) is an integrated telephone numbering plan for twenty-five regions in twenty countries, primarily in North America and the Caribbean. This group is historically known as World Numbering Zone 1 and has the country code 1. Some North American countries, most notably Mexico, do not participate in the NANP.

The concepts of the NANP were devised originally during the 1940s by the American Telephone and Telegraph Company (AT&T) for the Bell System and the independent telephone companies in North America in Operator Toll Dialing. The first task was to unify the diverse local telephone numbering plans that had been established during the preceding decades, with the goal to speed call completion times and decrease the costs for long-distance calling, by reducing manual labor by switchboard operators.

 Eventually, it prepared the continent for direct-dialing of long-distance calls by customers, first possible in 1951, which expanded across the nation during the decades following. AT&T continued to administer the continental numbering plan and the technical infrastructure until the end of the Bell System, when operation was delegated to the North American Numbering Plan Administration (NANPA), a service that has been procured from the private sector by the Federal Communications Commission (FCC) in the United States. Each participating country forms a regulatory authority that has plenary control of local numbering resources The FCC also serves as the U.S. regulator. Canadian numbering decisions are made by the Canadian Numbering Administration Consortium.

The NANP divides the territories of its members into numbering plan areas (NPAs) which are encoded numerically with a three-digit telephone number prefix, commonly termed the area code. Each telephone is assigned a seven-digit telephone number unique only within its respective numbering plan area. The telephone number consists of a three-digit central office (or exchange) code and a four-digit station number. The combination of an area code and the telephone number serves as a destination routing address in the public switched telephone network (PSTN). The North American Numbering Plan conforms with International Telecommunication Union (ITU) Recommendation E.164, which establishes an international numbering framework.

From the Bell System's beginnings in 1876 and throughout the first part of the 20th century, telephone networks grew from essentially local or regional telephone systems. These systems expanded by growing their subscriber bases, as well as enlarging their service areas by implementing additional local exchanges that were interconnected with tie trunks. It was the responsibility of each local administration to devise telephone numbering plans that accommodated the local requirements and growth. 

As a result, the North American telephone service industry developed into an unorganized set of many differing local numbering systems. The diversity impeded the efficient operation and interconnection of exchanges into a nationwide system for long-distance telephone communication. By the 1940s, the Bell System set out to unify the various existing numbering plans to provide a unified, systematic concept for routing telephone calls across the nation, and to provide efficient long-distance service that eventually did not require the involvement of switchboard operators.

In October 1947, AT&T published the first nationwide numbering plan in coordination with the independent telephone operators. The plan divided most of North America into eighty-six numbering plan areas (NPAs). Each NPA was assigned a unique three-digit code, typically termed NPA code or simply area code. These codes were first used in Operator Toll Dialing by long-distance operators in establishing calls via trunks between toll offices. The goal of automatic service required additional technical advances in the latest generation of toll-switching systems, completed by the early 1950s, and installation of new toll-switching systems in most numbering plan areas. The first customer-dialed direct call using an area code was made on November 10, 1951, from Englewood, New Jersey, to Alameda, California. Direct distance dialing (DDD) was introduced subsequently across the country. By the early 1960s, DDD had become commonplace in cities and most towns in the United States and Canada. By 1967, the number of assigned area codes had grown to 129.

The status of the network of the 1960s was reflected by a new name used in technical documentation: North American Integrated Network. By 1975, the numbering plan was referred to as the North American Numbering Plan, resulting in the well-known initialism NANP, as other countries sought or considered joining the standardization.

 A complete list of all of the area codes can be found at the link below:

https://en.m.wikipedia.org/wiki/List_of_North_American_Numbering_Plan_area_codes

Today, there are over 999 area codes in use, a huge change from my childhood, when NON existed. For the record, our “area code” was “Prospect”, which apparently still functioned until the early 1950’s.

A few years after I was born, we still had a party line, and rotary dial phones were still in use until sometime in the early 1990’s.

The only question that I have for you know is this:

“Can you hear me now”?

Verizon Wireless - Can You Hear Me Now? Commercial (2002)