Confidentiality is the property of preventing unauthorized access or disclosure of data. Encryption is a method of transforming data into an unreadable format that can only be decrypted by authorized parties who have the correct key. Encryption can increase the confidentiality of data communication across the network by making it harder for attackers to intercept or eavesdrop on the data. Reference: Network+ Study Guide Objective 4.1: Summarize the purposes of physical security devices. Subobjective: Encryption.