The Alcatel experience of DSL deployment

Incumbent telcos desire to make the optimum use of their existing copper pair networks in order to deliver the new services required by their customers. This enables the incumbent telcos to compete with new operators who use alternative technologies, without incurring the very high costs of building new infrastructure. The technologies used by the new operators include cable TV systems, which can be extended to offer not only broadcast TV, but also telephony, fast Internet access and other data services, as well as video on demand. Other competing technologies are satellite, which can be combined with a telephony back channel to provide a limited interactive service, radio microwave distribution, and all fibre systems. However, the price performance combination of the DSL technologies is so attractive that even new operators are increasingly making use of them. There is now a range of different DSL technologies available for high speed transmission over copper, which are appropriate to the requirements of different customers. These include HDSL and SDSL for symmetric services mainly to business customers, ADSL for asymmetric services to residential and SOHO customers, and VDSL for very high-rate symmetric or asymmetric services to business or residential customers. VDSL has a relatively short range, and is thus often operated from street cabinets, although operation from exchange buildings is sometimes done. HDSL, SDSL, and ADSL can be operated from exchange buildings or street cabinets as appropriate. This paper outlines the range of Alcatel DSL products, and the experience of their deployment.