Fine-grained data integrity checking methods could isolate a portion of corrupted data segments and assure the integrity of other data at the same time.They could mitigate the disastrous effect that all the data become invalid caused by accidental errors or intentional forging modification.The issues of integrity checking for fine-grained data are summarized at first.Based on the finite projective geometry theory

a novel data integrity checking method (integrity indication code) is proposed to improve the error indication efficiency.The basic idea of the method is mapping the relationship of points and lines in finite projective geometry to the check relationship of hashes and data objects

and achieving uniform crossover of all the hashes.The performances analysis and experimental results show that this code is effective with higher compression ratio.