Multiple data frames are interleaved and transmitted together. Good for error tolerance, since bursty noise doesn't wipe out a complete frame, but small parts of multiple ones, which then can individually be fixed by their Reed-Solomon error correction codes. But it adds latency, since the sender has to collect data from multiple frames to combine, and the receiver has to receive the entire block before it can be decoded, instead of transmitting each frame as it arrives.

Thanks.