UNE-ETS 300324-4ED1

V interfaces at the digital Local Exchange (LE);V5.1 interface for the support of Access Network (AN);Part 4: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification for the network layer (AN side) (Endorsed by Asociación Espanola de Normalización in June of 2022.)