The invention relates to a method for performing network functions for a subscriber-sided (CPE) network access unit (ONT) in a telecommunication's access network with a central unit (CO, OLT), a distribution network (AN), and a multiple of network-sided network termination units (DPD) with subscriber-sided network access units (ONT) connected or connectable thereto, in which network a bidirectional communication path (1) is present between the central unit (CO) and that network-sided network termination unit (DPD), to which the subscriber-sided network access unit (ONT) under consideration is connected, in which for performing network functions a further bidirectional communication path (2) between the subscriber-sided network access unit (ONT) under consideration and the corresponding network-sided network termination unit (DPD) is used in connection with the bidirectional communication path (1) between the central unit (CO, OLT) and that network-sided network termination unit (DPD), as well as to a telecommunication's access network (FIG. 1), a central unit (CO, OLT), a network-sided network termination unit (DPD), and a subscriber-sided network access unit (ONT).