Data transfer device and data transfer system using adaptive compression algorithm

A data transfer system comprising a data transfer device configured to transfer compressed data and a receiver device configured to receive compressed data through a network, wherein the data transfer device includes:

• a compression processing part configured to compress data in accordance with an optimum compression algorithm, which is selected from among a plurality of compression algorithms by way of comparison of compressibility and a network bandwidth, with respect to a central processing unit (CPU) constraint process preferential to a network (NW) an NW bandwidth-constraint process;
• a temporary hold part configured to temporarily hold compressed data;
• and
• a transfer part configured to transfer compressed data, read from the temporary hold part, through the network,
• wherein the compression processing part stores compressed data according to the NW bandwidth-constraint process in the temporary hold part when an amount of compressed data held by the temporary hold part is smaller than a predetermined value, and
• wherein the compression processing part stores compressed data according to the CPU-constraint process in the temporary hold part when the amount of compressed data held by the temporary hold part is larger than the predetermined value,
• wherein the optimum compression algorithm is selected based on a product using a parallelism P, a compression processing speed C and a compressibility R compared to a network bandwidth N, wherein the CPU-constraint process is selected when PRC<N while the NW bandwidth-constraint process is selected when PRC≧N.

A data compression transfer method, further comprising:

• selecting an optimum compression algorithm from among a plurality of compression algorithms by way of comparison of compressibility and a network bandwidth with respect to a central processing unit (CPU)-constraint process preferential to a network (NW) bandwidth-constraint process, wherein the optimum compression algorithm is given a priority preferring the CPU-constraint process, imposing a constraint to a compression processing speed rather than a transfer processing speed, to the NW bandwidth-constraint process imposing a constraint to a transfer processing speed rather than a compression processing speed;
• compressing data according to the optimum compression algorithm:
• holding compressed data in a temporary hold part before a transfer process;
• comparing an amount of compressed data held by the temporary hold part with a predetermined value;
• storing compressed data according to the NW bandwidth-constraint process in the temporary hold part when the amount of compressed data held by the temporary hold part is smaller than the predetermined value;
• and
• storing compressed data according to the CPU-constraint process in the temporary hold part when the amount of compressed data held by the temporary hold part is larger than the predetermined value;
• wherein the optimum compression algorithm is selected based on a product using a parallelism P, a compression processing speed C and a compressibility R compared to a network bandwidth N, wherein the CPU-constraint process is selected when PRC<N while the NW bandwidth-constraint process is selected when PRC≧N.