Rather confusingly, the SDSL acronym sometimes refers to Single line DSL. SDSL needs just one twisted pair line, whereas some other earlier DSL standards needed two, or even three pairs.
is almost restricted to business use, costing more than ADSL
and offering the home user
no significant advantage. 1 MBIT ADSL
typically offers a 256 kbps upstream
that is more than sufficient for home use.