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.