Abstract: A data sending/receiving system having an information providing apparatus including a content data storage unit to store content data, and a streaming data generator to generate streaming transmission data from content data. The system also includes a streaming interface, a download file generator to generate a download file of content data and a download interface for the download file, which is connected to a data receiving terminal including a storage control circuit to control storage of content data into a content data recording unit. The system also include a packet information recording unit to record data packet ID information and a packet resend requesting circuit to request for resending a missing packet, via a network. Defect-free data can be transmitted with the real-time signal transmission being assured even when data is received, for recording, via a low-reliability network.

Abstract: A method is provided for routing data packets across a multi-layer network which includes a plurality of nodes, a logical level provided with a plurality of logical links and a physical level provided with a plurality of physical links, each of the logical links corresponding to at least one of the physical links, the method comprising the steps of assigning a weight to each logical link with respect to a first critical constraint in the logical level, refining the weight assigned to each logical link with respect to a second critical constraint in the physical level and, based on the weights assigned to each link, computing a path at the logical level connecting a start node to an end node for the transport of the data packets.