THE CONCEPT OF HASH VALUE AND THE COLLISION OF HASH VALUE AS THE WAY TO PROVIDE UNASSAILABILITY OF DIGITAL EVIDENCE

The evidence used to prove the material fact which is subject to the criminal procedure should not be changed until it is brought before the court. It is relatively easy to ensure the accuracy of physical evidences by taking them into judicial custody. However, it is difficult to ensure the accuracy of the digital evidence since it is easy to copy and modify it. Digital evidences are used to provide the technological means to ensure accuracy. The hash value, which provides a one-way summarization value, can be applied to digital evidence such as a fingerprint and helps to ensure the accuracy of the numerical evidence. However, a collision of hash value, known as the hash value conflict, which occurs when two different digital data have the same hash value, is a problematic area in ensuring the accuracy of numerical evidence. In this study, the concept of summary value as a means of ensuring the accuracy of numerical evidence will be explained and the possible effects of the hash value collision will be discussed