This standard defines the North American network access transmission model to be used in
evaluating performance of DSL modems. The standard can be applied to both splittered and
splitterless xDSL systems. The model is described in terms similar to prior ANSI and ITU modem
test standards (e.g., V.56bis) and allows comparison of DSL modem performance in terms of
percent network coverage. This model is intended for use by network service providers,
magazine product reviewers, users and designers to evaluate and compare modem performance.