subject: What Happens When You Make A Long Distance Call? [print this page] Few people remember the tedious process through which long distance calls were once conducted. With today's wireless devices and telecommunications technology, calling someone in another country is as simple as picking up your phone and dialing their number. To say it wasn't always so easy is an understatement. Indeed, there was once a time when speaking to a friend or relative in the next town required the help of a human operator.
Computerized exchanges now handle the tasks that were once performed by people. But, to better understand how long distance calls are processed today, it's worth revisiting how they were completed a generation ago. In this article, we'll describe the process as well as the industry's evolution from using a human operator to a digital switch.
Early Local And Long Distance Calling "Technology"
In the "old days," each city or town had a central office in which operators sat in front of switchboards. These switchboards were filled with outlets, one for each person in the town. Whenever a person wanted to make a call, they would pick up their handset and a light would go on above their outlet. The operator would see the light, plug in her personal line, and ask the person with whom they wanted to connect. Then, the operator would plug her line into the destination party's outlet and ring their phone. When the intended recipient answered, the operator would connect the two outlets so the parties could speak with one another.
When a person wanted to make a long distance call, the same process would occur with a few additional steps. The operator would need to speak with someone in a special long distance office who would connect her to another city's central office based upon the destination number's area code. An operator in that central office would form a connection to the recipient before connecting the originating caller.
The Evolution Of Computerized Switching
It wasn't long before automation would replace much of the manual work involved in the process described above. Switches were introduced first into local central offices, thereby eliminating the need for human operators. To make a long distance call, a person would dial "0" and speak directly to an operator in the long distance office. Soon, those operators were also eliminated. Computerized switches were able to make the connections automatically, allowing for faster and more reliable service.
Today, the copper lines that were once used to connect callers with their intended parties have been replaced by high-capacity fiber optic cables. While the copper lines could only support one conversation at a time, fiber optic cables can support multiple conversations simultaneously. Predictably, efficiency and service improved while the costs of placing long distance calls declined. So seamless has the process become that most of us give little consideration to the enormous technology which supports it.
