A DSL communication apparatus with lifeline functionality is provided, the DSL communication apparatus (3) in particular being suitable for CVoDSL ("Channelized Voice over Digital Subscriber Line") transmission. The DSL communication apparatus (3) comprises a central processing unit (11) which detects a local power failure state of a local power supply unit (23) being associated with the DSL communication apparatus (3). In this case, the central processing unit (11) changes the operation of the DSL communication apparatus (3) from a normal operation mode to an intermediate operation mode, generates an interrupt for stopping a voice coprocessor unit (8), initializes a download of a lifeline operation firmware from a FLASH memory (12) to the voice coprocessor unit (8), and then starts a new initialization of the voice coprocessor unit (8). Thereafter, the central processing unit (11) changes the operation of the DSL communication apparatus (3) from the intermediate operation mode to the lifeline operation mode by switching the power supply of the DSL communication apparatus (3) from the local power supply unit (23) to an auxiliary power supply unit (20) being coupled to the transmission line (1).