| 摘要 |
<p>A method and apparatus is provided for distributing data elements from a data source (N) to receivers (H1 to H9) over a communications network. A data element may be one at least two types, including a type conveying a full data set and a type conveying a data set comprising only corresponding meta-information. The meta-information data set includes at least a unique identifier for the full data set to which it corresponds. A hierarchy of forwarding computers (P, C1 to C3) is provided to forward a data element supplied by a data source (N) to sets of receivers (H1 to H9). Each forwarding computer (P, C1 to C3) is arranged with access to a respective forwarding table for recording the requirements of receivers to receive data elements of one of the available types, each forwarding computer (P, C1 to C3) forwarding a received data element according to the contents of the respective forwarding table. A receiver (H1 to H9) of a meta-information data element may initiate a search by the forwarding computers (P, C1 to C3) for a copy of a corresponding full data set stored at another receiver (H1 to H9).</p> |
