Integrity

Integrity-

Integrity refers to the ability to prevent our data from being changed in an unauthorized or undesirable manner.   This  could   mean   the  unauthorized change  or  deletion of our  data  or  portions of our  data,  or it could  mean  an authorized, but undesirable, change or deletion of our data. To maintain integrity, we not only need to have the  means  to prevent  unauthorized changes to our data but also need the ability to reverse authorized changes that  need to be undone.  We can see a good example of mechanisms that allow us to control integrity in the file systems of many modern operating systems such as Windows and Linux. For purposes  of  preventing  unauthorized changes,  such  systems often  implement  permissions  that  restrict what  actions  an unauthorized user can perform on a given file. Additionally, some such systems, and many applications, such as databases, can allow us to undo or roll back changes that are undesirable.  Integrity  is particularly  important when  we  are discussing  the  data  that  provides  the foundation for other  decisions.  If an attacker were to alter the data that contained the results  of medical  tests, we might  see the wrong  treatment prescribed,  potentially resulting in the death of the patient