A system has a processor configured to be capable of read and write to a main memory, a storage configured to transmit stored data per block on an I/O bus, and a protocol processing apparatus connected to the I/O bus and configured to perform a communication protocol process on behalf of the processor. The processor includes a specifying part configured to specify data per block to be transmitted from the storage, and an indicating part configured to indicate data transfer from the storage to the protocol processing apparatus by specifying address information of the protocol processing apparatus. The protocol processing apparatus includes a receiving part configured to directly receive data transferred per block from the storage to the I/O bus, without relaying the main memory, and a network processing part configured to transmit the data received per block by the receiving part over a network per packet.