The subject matter discloses a method, comprising obtaining a current retention time of storage associated with a digital recorder; obtaining current bitrates of channels used to transmit video captured by edge devices communicating with the digital recorder. The method then determines change in compression rates to be allocated to at least a portion of the channels according to the current retention time and the current bitrates and transmits the change in compression rates to be allocated to the channels to edge devices communicating with the digital recorder. The method can be implemented in a system in which several digital recorders use the same storage.