There is provided mechanisms for time-synchronized communication of packets between a first substation and a second substation interconnected by a communication channel. Samples obtained within the second substation are provided with time information associated with a common reference clock and sent to the first substation, at which a time-wise synchronization of the received samples with samples obtained within the first substation is performed by means of the time information and a time difference between the common reference clock and a local reference clock of the first substation.