Client Buffering Techniques for Scalable Video Broadcasting Over Broadband Networks With Low User Delay S.-H. Gary Chan and S.-H. Ivan Yeung, IEEE Transactions on Broadcasting, March 2002.

Introduction Periodical Broadcast Harmonic Broadcasting Pyramid Broadcasting Skyscraper Broadcasting Join-and Stream (JAS) Stream-bundling

Pyramid Broadcasting Each video is divided into K segments with the size of the i th segment being  times of the ( i -1) th segment (   1) The total server bandwidth is accordingly divided into K different streaming channels with the same bandwidth

Pyramid Broadcasting (Cont.)  = 2 S1S1 S2S2 S3S3 15 min30 min60 min Movie Length = S = S 1 + S 2 + S 3 S1S1 S1S1 S1S1 S2S2 S2S2 S1S1 C0C0 C1C1 C2C2 S3S3 S3S3 Advantage: Given a certain user maximum delay, it achieve low bandwidth requirement Drawback: Large buffer size is required (75% of the movie length)

Harmonic Broadcasting The total bandwidth(B) allocated for the movie is as follows: d B = b + b/2 + b/3 + b/4 = 2.083b

Skyscraper Broadcasting Skyscraper broadcasting scheme allocates fixed bandwidth --- the consumption rate of a video for each logical channel The segment size is determined by a recursive function, whose materialized serious is as follows: [1, 2, 2, 5, 5, 25, 25, 25, 52, 52, …]

Skyscraper Broadcasting (Cont.)

Join-and Stream (JAS) The video is broadcast in a staggered manner at regular offset point of T s minutes apart, and hence the number of multicast streams allocated for this movie is  T h /T s 

JAS (Cont.) (Movie Length) User maximum waiting time x Buffering x Unicast Stream => B max = Tx - D max

Stream-Bundling Broadcasting A user arriving into the system is served in the next mini-slot. The server streams are grouped (I.e., bundled) into multicast channels of increasing bandwidth with an increment of b 0

Stream-Bundling (Cont.) Multicast/broadcast (b 0 ) (2b 0 ) b0b0 (T s /D max – 1)* b 0

Stream-Bundling (Cont.) Average bundled streams is Total number of streams S = S achieves it minimum of at B = T s - D max (T s /D max – 1) / 2 (T s /D max – 1) / 2 + T h / T s

Experimental Result

Comparison