| 摘要 |
<p>A higher network sends a base stream of a data stream to a first network node, and sends an enhancement stream of the data stream to a second network node. The first network node transmits the base stream over a multicast channel and the second network node transmits the enhanced stream in synchronism with the transmitted base stream over a unicast channel. Various options are detailed for how this synchronism is achieved, and the second network node need only transmit the higher bit-rate enhancement stream on user request or if network conditions permit. A user equipment receives the base and enhancement streams, combines them, and displays the combined stream to a user at a graphical display interface. Various apparatus, methods, and computer programs are detailed for various nodes and the user equipment.</p> |
