A symmetric Digital Subscriber Line | Electronics Seminar Topic
A symmetric Digital Subscriber Line
ADSL technology is asymmetric. It allows more bandwidth
downstream from an NSP’s central office to customer site than upstream from the
subscriber to the central office. This asymmetry companied with always-on
access which eliminates call setup makes ADSL ideal for Internet surfing, video
on demand, and remote LAN access. Uses of this application typically download
much more information than they send.
ADSL transmits more than 6 Mbps to a subscriber, and as much
as 640Kbps more in both directions. Such rate expands existing access capacity
by a factor of 50 or more wit out new cabling.
ADSL can literally transform the
existing public information network from one limited to voice, text, and
low-resolution graphics to a powerful ubiquitous system capable of bringing
multimedia, including full motion video to every home this century.
ADSL will play a crucial role over the next decade or more
as telephone companies enter new markets for delivery information in video and
multimedia formats. New broadband cabling will take decades to reach all
prospective subscribers.
Success of these new services will depend on reaching
as many subscribers as possible during the first few years. By bringing movies,
television, video catalogues, remote CD-ROMs, corporate LANs and the internet
into homes and small businesses, ADSL will makes these markets viable and
profitable for telephone company and application suppliers.
