Video on demand ipbased services leased lines nisdn services pstn subscriber line copper twisted pair sni service node interface handshake procedures. In the past years, dsl technologies have attracted a great deal of attention as the access solution of the. Adsl asymmetric digital subscriber line is a technology for transmitting digital information at a high bandwidth on existing phone lines to homes and businesses. With its inside track and extensive level of detail, understanding digital subscriber line technology will be indispensable to telecom and datacom engineers at every level. A dsl requires two modems, one at the phone companies end and one at the subscribers end. Glossary of terms for the electric utility industry. Dsl increases data transmission rates by a factor of twenty or more by sending signals in. Digital subscriber line revolvy brain revolvybrain. Dsl increases data transmission rates by a factor of twenty or more by sending signals in previously unused high frequencies. The two main types of broadband technology that have pervaded the market are asymmetric digital subscriber line adsl and cable modems. Digital subscriber line dsl access service connection point.
Digital subscriber line dsl is a last mile service that allows consumers to access the internet by using their existing telephone lines. In telecommunications marketing, the term dsl is widely understood to mean asymmetric digital subscriber line adsl, the most commonly installed dsl technology, for internet access. Digital subscriber line development has been most rewarding. Understanding digital subscriber line technology types of dsls dsl technology began with 144 kbs basic rate isdn bri, and has evolved to 1. The book is an attempt to give you complete information and knowledge about digital subscriber line technology. The most popular implementation of dsl today is asymmetric digital subscriber. Dsl provides dedicated, pointtopoint, public network access.
Then, breakthrough concepts in digital transmission were enabled by enormous advances in verylargescale integrated vlsi circuits and digital signal processing dsp. Dsl collectively refers to a group of technologies that utilize the unused bandwidth in the existing copper access network to deliver highspeed data services from the distribution center, or central office, to the end user. Digital subscriber line dsl is currently the most widespread technique for delivering broadband internet to homes worldwide. Digital subscriber line dsl technology is a copper loop transmission technology, which satisfies bottleneck problems often associated with the last mile between the network and the service providers.
Dsl digital subscriber line is a modem technology that uses existing telephone lines to transport highbandwidth data, such as. Digital subscriber line dsl technology transforms an ordinary telephone line into a broadband communications link, much like adding express lanes to an existing highway. Understanding digital subscriber line technology, volume 1. Understanding digital subscriber line technology pearson. Dsl digital subscriber line is a technology for bringing high bandwidth information to homes and small businesses over ordinary copper telephone lines. Unlike regular dialup phone service, adsl provides continouslyavailable, always on connection. Understanding digital subscriber line technology thomas starr, john m. Pdf understanding digital subscriber line technology book. Hdsl, symmetric dsl sdsl, asymmetric dsl adsl or very high speed dsl vdsl. Learn about digital subscriber line dsl, and why this highbandwidth technology is important to the future of data delivery. Fast guide to dsl digital subscriber line reference. Digital subscriber line dsl access service connection point the term digital subscriber line dsl access service connection point is a location designated by the company that serves as an aggregation point for the collection of company wbits traffic from multiple digital subscriber line access multiplexers. Pdf adsl asymmetric digital subscriber line is a technology that allows transmission at 8.
Digital subscriber lines an overview sciencedirect topics. Understanding digital subscriber line technology informit. Find out how dsl uses extra bandwidth to provide a. Dsl digital subscriber line digital subscriber line or digital subscriber loopdsl is a type of highspeed internet technology that enables transmission of digital data via the wires of a telephone network. All dsl technology can be subdivided into one of two types. Adsl uses standard phone lines to provide high speed data communications. It also offers a comprehensible explanation of issues in this growing field to managers, marketing experts, and consumers of dsl technology. Dsl vs adsl dsl digital subscriber line is the generic term for services that provide internet connections using digital data connections between a modem and a phone line. Symmetric digital subscriber line sdsl the term symmetric digital subscriber line sdsl denotes anaccess technology that allows high speed data to be sent over local exchange service facilities. Digital subscriber line dsl is a technology that transports highbandwidth data over a simple telephone line that is directly connected to a modem. Hdsl high speed digital subscriber line is a particular type of sdsl usually providing 2 mbits transmission in both downstream and upstream directions vdsl very high speed digital subscriber line is able to operate at very high speed e.
Digital subscriber line dsl greater data speed over the existing infrastructure. Asymmetric digital subscriber line adsl can supply the necessary bandwidth for applications such as. Asymmetric digital subscriber line adsl is a new modem technology that converts existing twistedpair telephone lines into access paths for highspeed communications of various sorts. This is an introductory tutorial, which covers the basics of the dsl technology. Digital subscriber line dsl technology transmits data over phone lines without interfering with voice service. What used to take minutes or hours to download will take just seconds or minutes. Digital subscriber line dsl technology provides instant internet and network access at speeds up to 50 times faster than a 28. Dsl technology achieves broadband speeds over the most universal network media in the world. Digital subscriber line a digital subscriber line makes use of the current copper infrastructure to supply broadband services. You need to know if what you are purchasing is the best choice for what you wish to accomplish. Both these technologies are a huge leap from the days of the 56 kbps dialup connections. This paper addresses basic features of xdsl technologies, focussing on modulation techniques, access network architecture and deployment problems.
This technology is designed to solve the most severe bottleneck in the data access network between the central office and the customer, or enduser. Dsl digital subscriber line is a modem technology that uses existing telephone lines to transport highbandwidth data, such as multimedia and video, to service subscribers. Digital subscriber line dsl is a broadband connection that uses the existing telephone line. It was clear that digital subscriber line dsl technology would start catching on at some point with small and mediumsize business users as a way to speed up bandwidth in pc networks. Leading experts in the field have come together to share their insights in a single volume, explaining the past, present. Provides an overview of the technology and a description of the main types of dsl in use today. The use of the term modem is not entirely correct because technically a dsl modem does not do.
The most promising of the dsl technologies is adsl or asymmetric digital subscriber line. Adsl has been effectively shown to meet the demands for high speed internet access without. What is an asymmetric digital subscriber line adsl. Each prospective user should be aware of the issues associated the technology and method they are using to be better informed. Pdf understanding digital subscriber line technology. Asymmetric digital subscriber line shdsl singlepair highspeed digital subscriber line vdsl very high speed digital subscriber line bisdn services video services, e. It is asymmetric because the upload and download speeds are not. Difference between dsl and adsl difference between. Vdsl very high bitrate digital subscriber line broadband has revolutionized the way we view and use the internet. Quadrature amplitude modulation topic quadrature amplitude modulation qam is the name of a family of digital modulation methods and a related family of analog modulation methods widely used in. Digital subscriber line technology is a copperloop transmission technology that solves the bottleneck problem often associated with the last mile between network service providers and the users of those network services.
Find out how dsl uses extra bandwidth to provide a fast internet connection without taking over your phone. Whats great about dsl, is that even when the phone line is in use, there is no interruption, and you can still experience a high speed internet connection even when you are making calls. Asymmetric digital subscriber line adsl definition asymmetric digital subscriber line adsl is a new modem technology that converts existing twistedpair telephone lines into access paths for highspeed communications of various sorts. Overview adsl can transmit more than 6 mbps to a subscriber enough to provide. The term digital subscriber line dsl access service connection point is a. Asymmetric digital subscriber line adsl is an advanced modem technology that utilizes different frequency spectrums to simultaneously transmit highspeed voice and data over the same copper loop. A separate phone line is not required for adsl service. Assuming your home or small business is close enough to a telephone company. In 1975, it was believed that 20 kbs was the highest data rate that could be transmitted via telephone lines.
Asymmetric digital subscriber line adsl is a type of dsl technology that provides greater bandwidth and provides higherspeed transmission over traditional copper telephone wires than conventional voice band modem. Network architecture, deployment problems and technical solutions vladimir krsti, mirjana stojanovi institut mihajlo pupin, beograd i introduction one of the most talkedabout areas in the telecommunications industry today is digital subscriber line dsl technology. By the end of 2010, over 300 million customers were served with dsl, a number representing approximately 60% of global broadband customers. Digital subscriber line technology by irmgard jankowski. Adsl asymmetric digital subscriber line is a technology that allows transmission at 8. While both dsl and dialup internet leverage existing telephone lines, dsl uses a frequency that allows calls and data to be transfered at the same time without interference allowing for users to both talk on their phone and use the internet. This allows for filesharing, and the transmission of pictures and graphics, multimedia data, audio and video conferencing and much more. Article pdf available in ieee communications magazine 385. Adsl upstream speeds from the user normally top out at 128kbps and downstream to the user at no more than 1. Focus on adsl focuses on asymmetric dsl, providing details on how this technology works. Communication devices asymmetric digital subscriber line adsl modems can be used for transmitting digital signals over a local dedicated telephone line, provided there is a telephone office nearbyin theory, within 5,500 metres 18,000 feet but in practice about a third of that distance. This group of technologies is frequently referred to as xdsl.