|  |  | Encryption is used to achieve four main results. Integrity ensures that the data has not been altered en route by either a hacker or an error. Privacy ensures that only the intended participants can read the data. Authentication identifies the party who sent the information. 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.