Checksum 101: A bit of information about Checksums

Checksum 101: A bit of information about Checksums. Ross Spencer. Archives NZ Workshop. 2 October 2016.
    A slide presentation providing very good information on checksums. Why do we use checksums:

• Policy: Provides Integrity
• Moving files: Validation after the move
• Working with files: Uniquely identifying what we’re working with
• Security:  a by-product of file integrity

An algorithm does the computing bit, and there are a variety of types, MD5, CRC32, SHA, etc. A checksum algorithm is a one way function that can't be reversed. DROID can handle MD5, SHA1, and SHA256.  Why use multiple checksums? This helps to avoid potential collisions, though the probabilities are low. The presentation shows the different type of checksums and how they are generated.

Checksums will ensure uniqueness. We can automate processes better with file checksums. Some people may have a preference of which checksums to use. Using the checksums will help future proof the systems and provide greater security

Digital Preservation Matters.