ADSL AND XDSL TYPES OF DSL CONNECTIONS AND DIFFERENCES
The technology ADSL , Asymmetric Digital Subscriber Line is a technology based on copper pair and the normal telephone line, making the classimo copper pair (last mile), a high-speed line. The technology ADSL uses the frequency spectra that are not used for the transport of voice in traditional telephone lines, and that until a few years or are not being used. The technology ADSL allows you to create an additional data channel for high-speed transport of information, without losing the characteristics of traditional telephone communication, thus allowing the user to be able to use the normal telephone line. The term
DSL ( Digital Subscriber Line ) , coined by Bellcore in 1989 defines a modem or a transmission mode that is converted to digital. The technology ADSL is part of a group of technologies defined xDSL developed for the transmission of high speed data on telephone wires, allowing a high velocity flow of asymmetric information on the local network. Technologies Group of
xDSL connections can differentiate into Asymmetric and symmetric connections, and are divided as follows:
ADSL : ADSL technology converts the twisted pair copper telephone connection in a transmission medium for high speed data transmission of multimedia applications by transforming a network created for voice transmission in a network for the transmission of any type of information without the need to create a new network and infrastructure.
RADSL : The technology RADSL is a variant of the technology, ADSL and allows to automatically adjust the speed of the data transmission based on the quality of the signal.
VDSL / VHDSL : This technology is also called the principle BDSL VADSL system delivers high speed, superior to any other xDSL technology, but only over short distances. The technology VDSL or VHDSL can reach downstream speeds of 52 Mbps over distances of 300 meters, and 13 Mbps only if it extends to 1,500 meters.
HDSL : HDSL technology allows the transmission of frames in T1 or E1 lines of twisted copper pairs (T1 E1 requires two three), using advanced modulation techniques, and can reach a distance of nearly 4 KM without the aid repeaters, it can reach a speed of 1.5 Mbps or 2 Mbps SHDSL
: Technology SHDSL technology is similar to HDSL and allows the transmission of a single pair of copper and supports simultaneous transmission of E1 and T1 voice and frame.
IDSL: Technology ISDL is an improved version of the ISDN service and allows speeds of 144Kbps to distances of 7 or 8 km.
Main elements for ADSL connection
3 are the main elements for the connection ADSL , and that allow the proper operation of the technology ADSL , these are:
- ADSL modem
- ADSL filter
- DSLAM ( Digital Subscriber Line Access Multiplexer ).
The voice and data services to travel within the copper pair of independent frequencies, the filter has the task of separating the telephone frequency from the frequency data. The modem ( modulator / demodulator ) ADSL receives data previously separated from the filter and delivers them to your computer or customer LAN. Cenrale is present in the digestive DSLAM, the DSLAM separates the frequencies for voice service and sends it to the traditional telephone network frequency data and sends it directly to the Internet.