UNE-TBR 2:1999

DIGITAL TERMINALS AND ACCESS (DTA). ATTACHMENT REQUIREMENTS FOR DATA TERMINAL EQUIPMENT (DTE) TO CONNECT TO PACKET SWITCHED PUBLIC DATA NETWORKS (PSPDNS) FOR CCITT RECOMMENDATION X.25 INTERFACES AT DATA SIGNALLING RATES UP TO 1 920 KBIT/S UTILIZING INTERFACES DERIVED FROM CCITT RECOMMENDATIONS X.21 AND X.21 BIS.