Résumé
Scalable video distribution schemes have been studied for quite some time. For very popular videos, open-loop broadcast schemes have been devised that partition each video into segments and periodically broadcast each segment on a different channel. Open-loop schemes provide excellent scalability as the number of channels required is independent of the number of clients. However, open-loop schemes typically do not support VCR functions. We will show for open-loop video distribution how, by adjusting the rate at which the segments are transmitted, one can provide VCR functionality. We consider deterministic and probabilistic support of VCR functions: depending on the segment rates chosen, the VCR functions are supported either 100% of the time or with very high probability. For the case of probabilistic support of PLAY and Fast-forward (FF) only, we model the reception process as a semi-Markov accumulation process. We are able to calculate a lower bound on the probability of successfully executing FF actions.