The purpose of this Recommendation is to define the Q3 interface between a network element for customer access (i.e. local exchange, access network) and the telecommunications management network (TMN) for the support of line and line circuit test functions and the associated management for ISDN and analogue customer accesses which are connected either directly to a local exchange or remotely at an access network and across V5.1 and/or V5.2 interfaces to a local exchange. The focus of this Recommendation is on defining an object model based on ITU-T Recommendations Q.824.0, Q.824.5, Q.831, and X.745. Existing protocols are used where possible. The definition of Operations System (OS) functionality is outside the scope of this Recommendation.