scope:

This part 1 of ETS 300 012 specifies requirements for the ISDN basic rate UNI including the physical, electrical and functional characteristics and the information exchange with higher layers. This ensures that interface implementations in an ISDN equipment for use with ISDN basic access is portable within Europe with regard to layer 1 interface aspects and that interworking with higher layer protocols for ISDN is supported. This ETS is applicable to equipment having interface I A or I B for the connection to the ISDN basic access intended to be installed on customer premises according to ITU-T Recommendation I.411 [9], this ETS is for application to interfaces at reference points S, T and S/T (coincident S and T) of the ISDN reference configuration. For the case where this ETS is applied to the T and the S/T reference point, the main body of this part 1 of the ETS and the parts 6 and 7 are normative. For the case where this ETS is applied to the S reference point, annex A to this part 1 of the standard is also normative.