This Recommendation deals with the general considerations and the requirements of the digital local line characteristics@ which are used between the line termination and the network termination@ to provide ISDN and xDSL services. The field of home network is not addressed in this Recommendation. Moreover@ this Recommendation describes the guidance for the use of multi-pair copper cable supporting shared multiple services such as ISDN/xDSL. The values used in this Recommendation are based on a number of DSL technologies as they are known at the moment of publication of this Recommendation. However@ the general principles are applicable to any type of DSL technology@ generally referred to as xDSL.