ADSL (Asymmetric Digital Subscriber Line) is currently the most widely used technology for Internet access by individuals.
Although it was not historically on this type of technology that the Triple Play offers were developed, that today is the first provider of this kind of offer.
ADSL is a technology developed to be able to pass data through the telephone lines (this allows then to re - use a network of already existing cable).
To do this, it uses the high frequency bands used by telephony (300-3400Hz), using multiplexing and modulation techniques suitable for telephone lines.
Using high frequencies of the phone line however involves the use of a filter on part and on the other of the phone line so that telephony signals does not disrupt the ADSL signals (and vice versa).
Flows are asymmetrical, which means that in ADSL, a Subscriber may send data (uplink) to a lower data rate can receive (way down).
The ADSL led to rates of 10 to 500 times greater than the previous techniques of Internet access for individuals (V92 : 56 kbps;) ADSL2+ : 25Mbps).
offering then the possibility ISPs to offer services other than Internet access, as is the case with the offers Triple Play.
Currently, Subscribers whose telephone line is not unbundled can, at best, that benefit from a rate of 2Mbps, which is not enough to get the audio/video stream.
Rates offered by ADSL are ideals rates because ADSL is very sensitive to the mitigation of telephone lines. So, more a line will be long between a Subscriber and its central office,
and less flow it can get via ADSL will be great. For even if the line is damaged, or has electronic devices