Encryption is used to achieve four main results.

  1. Integrity ensures that the data has not been altered en route by either a hacker or an error.
  2. Privacy ensures that only the intended participants can read the data.
  3. Authentication identifies the party who sent the information.
  4. Non-repudiation proves that the correct party did indeed send the information.

It is possible for a hacker to falsely authenticate himself if he acquires a username and password, but non-repudiation will indicate whether information came from the wrong source.