Digital subscriber line (DSL) is a type of technology that uses the local telephone network for digital data transmission. Unlike cable which comes through the cable lines, DSL is provided through the phone company. Therefore, the transmission happens simultaneously to the regular telephone transmissions. The reason that they don’t interfere with each other is that they operate on two different frequencies which allow for a complete separation. It is because of this that an individual can be on the phone and surfing the Internet at the same time.
The download speed for DSL — or the speed in which the service is provided to the consumer — is anywhere from 384 kbits/sec up to 20 Mbits/s. These vary, obviously, based on the type of wiring that is set up to the house, service-level implementation and line conditions. The upload speed for DSL — or the speed in which data sent from the consumer back to the provider — is always much smaller. It is because of this that the typical type of DSL that is installed is known as ADSL. This stands for asymmetric digital subscriber line and means that the download speed of DSL is faster than the upload speed.
A telephone relies on the low frequency regime which is around 5 kHz and below. DSL, though, relies on a high frequency regime upward of 25 kHz or greater. Because of this, the two can function simultaneously. However, to ensure that there is no high frequency sounds on the phone, a DSL filter is applied on each telephone outlet to guarantee that it doesn’t bother the consumer. It removes the high frequency band and guarantees that the consumer can use both the telephone and the Internet at the same time without complication.
One thing to note is that the distance in which the data has to travel does reduce the amount of upload and download capability. Modern day ADSL can handle upward of 24 Mbits/s over a 2 kilometer stretch of wire. However, when the wire is made to be longer than 2 kilometers (or anything longer than 1.25 miles), the data transfer becomes diminished and therefore, not as much can be done. It is because of this that, while the ADSL can have a great download rate, the farther the individual is from the service provider, the less that they are likely to get. Therefore, the service providers tend to advertise the low ball, but a consumer might get more. It all depends on the distance the information has to travel across the copper wires.
