DSL or Digital Subscriber Line, is a technology that uses standard copper telephone lines to deliver high-speed Internet access. ADSL installations will take approximately 7 days. SDSL installations will take approximately 30-45 days. DSL provides a dedicated service over a single telephone line.
Cable modems provide a dedicated service over a shared network.
While cable modems may have greater download bandwidth capabilities, the bandwidth is shared among all users and will vary, as more users in a neighborhood get online at the same time. DSL is provided using a dedicated circuit from the Telco to the end user. ADSL connections can be shared on an existing line. Line sharing greatly reduces the time frame for installing DSL service.