DEV Community

M.Ark
M.Ark

Posted on

Integrity Checks

Integrity Checks

An integrity check is a way to measure the consistency of a collection of data (a file, a picture, or a record). The integrity check performs a process called a hash function to take a snapshot of data at an instant in time. The integrity check uses the snapshot to ensure data remains unchanged.

A checksum is one example of a hash function. A checksum verifies the integrity of files, or strings of characters, before and after they transfer from one device to another across a local network or the Internet. Checksums simply convert each piece of information to a value and sum the total. To test the data integrity, a receiving system just repeats the process. If the two sums are equal, the data is valid (Figure 1). If they are not equal, a change occurred somewhere along the line (Figure 2).

Common hash functions include MD5, SHA-1, SHA-256, and SHA-512. These hash functions use complex mathematical algorithms. The hashed value is simply there for comparison. For example, after downloading a file, the user can verify the integrity of the file by comparing the hash values from the source with the one generated by any hash calculator.

Organizations use version control to prevent accidental changes by authorized users. Two users cannot update the same object. Objects can be files, database records, or transactions. For example, the first user to open a document has the permission to change that document; the second person has a read-only version.

Accurate backups help to maintain data integrity if data becomes corrupted. An organization needs to verify its backup process to ensure the integrity of the backup before data loss occurs.

Authorization determines who has access to an organization’s resources based on their need to know. For example, file permissions and user access controls ensure that only certain users can modify data. An administrator can set permissions for a file to read-only. As a result, a user accessing that file cannot make any changes.

Top comments (1)

Collapse
 
johnodhiambo profile image
JohnOdhiambo

Very informative