Patent ID: 7073092

Claim:
A channel adapter that is used in a disk array device and controls data exchange with an upper-level device, the channel adapter comprising: an internal memory that stores data from an external memory; a guarantee code computing unit that computes an input guarantee code in regard to data inputted to the internal memory and computes an output guarantee code in regard to data read from the internal memory, with the guarantee codes being retainable in the guarantee code computing unit; a communication unit that transmits the data read from the internal memory to the upper-level device; and a control unit which, in a case where partial data of the data read from the internal memory unit is to be retransmitted to the upper-level device, uses the communication unit to transmit the partial data to the upper-level device, compares the input guarantee code and the output guarantee code computed by the guarantee code computing unit in regard to the data read from the internal memory unit, and determines that transmission of the data read from the internal memory unit has been conducted normally in a case where both guarantee codes are in conformity.