In a multichannel transmission system, a process that diverts (drops) a portion of the multiplexed aggregate signal at an intermediate point, and introduces (inserts) a different signal for subsequent transmission in the same position, e.g., time slot or frequency band, previously occupied by the diverted signal. Note 1: Signals not of interest at the drop-and-insert point are not diverted. Note 2: The diverted signal may be demodulated or reinserted into another transmission system in the same or another time slot or frequency band. Note 3: The time slot or frequency band vacated by the diverted signal need not necessarily be re-occupied by another signal. Likewise, a previously unoccupied time slot or frequency band may be occupied by a signal inserted at the drop-and-insert point.