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| ==== abstract ==== | ==== abstract ==== | ||
| There has recently been and continues to be a large amount of work in | There has recently been and continues to be a large amount of work in | ||
| + | cellular commercial standards that is focused on multimedia delivery using | ||
| + | broadcast and multicast channels. The reasons for these standardization | ||
| + | efforts are self-evident: while cellular services become ever more popular | ||
| + | and as cellular multimedia applications grow richer, the available bandwidth | ||
| + | for delivering these services remains fairly limited, and thus | ||
| + | broadcast/multicast delivery is the only viable solution operators see to | ||
| + | this obvious revenue-threatening bottleneck. Examples of such commercial | ||
| + | standardization efforts include 3GPP MBMS, DVB-H IPDatacast, 3GPP2 BCMCS and | ||
| + | DMB. One of the primary challenges in using broadcast/multicast channels for | ||
| + | delivering multimedia is to provide a reliable solution that efficiently | ||
| + | uses the channel. For cellular unicast delivery, there are a number of | ||
| + | methods to assure reliability and efficiency, including automatic modulation | ||
| + | and error-correction adjustments at the physical layer, automatic | ||
| + | retransmission of lost radio packets, and automatic adjustments of transmit | ||
| + | power, all based on continual feedback from each individual receiver. | ||
| + | |||
| + | For cellular broadcast/multicast delivery, none of these methods are applicable, | ||
| + | and the primary method of providing reliability instead is the use of application-layer | ||
| + | FEC codes. In this talk we describe some of the broadcast/multicast services to | ||
| + | be offered and specifically how application-layer FEC codes provide reliability and | ||
| + | channel efficiency for each of the services. We also describe in some detail | ||
| + | Raptor R10, the application-layer FEC code that has been chosen by 3GPP MBMS | ||
| + | and DVB-H IPDatacast, and that is under consideration in all of the remaining cellular | ||
| + | standards that have not yet made a selection. | ||
| + | |||
| + | {{:en:group:seminars:luby1005.pdf|Full presentation}} | ||