The first step of long-reach ADSL: smart DSL technology, READSL

Long-reach DSL (LDSL) is a project in the ITU, with the objective to increase the reach of DSL solutions. Range extended ADSL (READ-SL) is the first step in the LDSL project, driven primarily by requirements for North America. READSL extends the connectivity of G.992.1/G.992.3 based ADSL up to 18 kft, increasing the ADSL reach by more than 3 kft under the severe crosstalk conditions typically experienced in the North American access network. To cope with the multiple physical layer field conditions, READSL uses "smart" DSL technology based on a selectable mask procedure. READSL is spectrally compatible with the basis systems in the North American Spectrum Management Standard T1.417, and requires minimum changes to both the G.992.1/G.992.3 standards and product platforms. This article reviews READSL as a subset of the LDSL project.