Harminic Broadcasting Protocol

Definition: Harmonic broadcasting divides a video into equal-size segments .

Harmonic broadcasting (HB) was initiated to divide the video into N equal-size segments and transmit them into logical channels of decreasing bandwidth. As illustrated in Figure 1, the i th video segment is put on the i th channel with a bandwidth of C/i . Client starts receiving data from each segment stream after it begins to download the first segment of the video.

Thus, the total bandwidth allocated for the video is given by

When the client is ready to consume S i , it will have received i – 1 slots of data from that segment and the last slot of that segment can be received during the segment playout time. If L is the length of the video, the start-up time T HB is equal to

The buffer requirement Buf HB can be calculated by eqn. (3):

where

However, it was found that HB could not always deliver all the data on time. Thus, the modified versions of HB called cautious harmonic broadcasting (CHB) and quasi-harmonic broadcasting (QHB) were proposed in to solve the problems.