This extra bandwidth ensures that more data can be sent over the same line. Digital subscriber line (DSL) technology is one of the most promising for supporting high-speed digital communication over the existing local loops. SDSL requires a special SDSL modem. endobj
There are also some automotive uses where data, voice, and music are sent over a direct current (DC) battery power line with special filters to filter out the line noise. ~��%O5C��@�RFhB��b����(�`�2$� �7���1 ��A���먻Ժ������O����t���2ba6O�֎��|u]�//�����"A:�!9sB�&v�OQ�� M�r��{?����ӯ���q���WN�\[��`J���T�Ҫr��i���Ls�s��͌��i���W5�z���/,����+\47��ν��4nw��Ub��DC�`A�0T�q����Y�:�>���2 ��/x����&�F�q(�p�U�(��gwN��n�pj���v��r[���L媊r�s��r�{n�MX�Z�6��x�䂮�[���p�9s�*PD�$�& Telephone lines only transmit a limited spectrum of signals (roughly 20 Hertz to 20,000 Hertz, for voice). SDSL works by sending digital pulses in the high-frequency area of telephone wires and can not operate simultaneously with voice connections over the same wires. It is fast because, in its line, copper wire is used. ISDN was not successful for many reasons with one being a very low speed. ADSL2+ services are capable of upload speeds of up to 2.5 Megabits per second (Annex M) or 1 Megabit per second. As Internet grew as a new business prospect then the telephone companies realize that they need more competitive product, so that they can offer both telephony and Internet over the same local loop. The large noise that results from the sum of crosstalk from all the other telephone lines reduced data rates. Typically, the uplink direction is four times slower than the downward direction. Devices can be a computer, printer or any other device that is capable to send and receive data. ADSL2+ Broadband runs much faster than standard ADSL. %����
On consumer’s end, a DSL modem modulates digital information from its computer to send it along phone lines. For visualization purpose, imagine any link as a line drawn between two points. This is where most digital-based technologies are derived. DSL is typically used by telephone companies to offer data, video, and voice services over these existing copper telephone lines. Line coding converts a sequence of bits to a digital signal. By splitting the bandwidth up in this way it effectively allows one connection to operate as if there were 247 modems connected to it, each of which operating at 4 kHz. HDSL (High bit-rate Digital Subscriber Line), one of the earliest forms of DSL, is used for wideband digital transmission within a corporate site and between the telephone company and a customer. It must not affect customers existing telephones and fax machines. Its aim is to maintain the high speed of the internet being transfered. This term is also known as power line carrier, power line digital subscriber line (PDSL), mains communication, power line telecom (PLT), power line networking (PLN), and broadband over power lines (BPL). Methods and systems are provided for managing communication between a digital subscriber line access multiplexer and customer devices. Digital Subscriber Line (DSL) DSL is a wireline transmission technology that transmits data faster over traditional copper telephone lines already installed to homes and businesses. Due to copper, it is only installed for limited distances. Digital Subscriber Line is a technology that assumes digital data does not require change into analog form and back. The word data refers to information presented in whatever form is agreed upon by the parties creating and using the data. 5. The local loop was originally intended mostly for the transmission of speech, encompassing an audio frequency range of 300 to 3400 hertz (commercial bandwidth). 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