Patent ID: 8180857

Claim:
A computer-implemented parallel file downloading method by which a file is downloaded to a node in a parallel downloading system including a plurality of nodes, the method comprising: obtaining node operation rates related to the plurality of the nodes connected to the system, wherein a node operation rate for a node j is calculated according to [Numerical formula 1] below: Active( j )=a time for which a node j actually operates/a measuring duration, [Numerical formula 1] wherein the Active(j) indicates a node operation rate of the node j; obtaining availability values related to blocks available at the plurality of nodes based on the node operation rates, wherein an availability value of a block is calculated according to [Numerical formula 2] below: Avail block ( f, i )=1−Π(1−Active( j )), (jεSources( f, i )), [Numerical formula 2] wherein the Sources(f, i) indicates a set of nodes having a block i of a file f, Π is a constant and the Avail block (f, i) indicates availability of the block i, which is a fragment of the file f; and if the node among the plurality of nodes requests to download the file, preferentially downloading, to the node, a block having a minimum availability value among blocks constituting the file.