What principle describes the control of access to sensitive or restricted information in communication systems?

The principle that describes the control of access to sensitive or restricted information in communication systems is confidentiality. Confidentiality ensures that information is not made available or disclosed to unauthorized individuals or systems. It is a critical component of information security, as it protects sensitive data from being accessed or viewed by individuals who do not have the proper authorization. Measures to maintain confidentiality may include encryption, access control lists, and user authentication, which help to ensure that only authorized personnel can access certain information.

While integrity and availability are also essential components of information security, they focus on different aspects. Integrity ensures that information remains accurate and unaltered, while availability ensures that information and resources are accessible to authorized users when needed. Security is a broader term that encompasses all aspects of protecting information, including confidentiality, integrity, and availability. Hence, confidentiality specifically relates to the control of access to sensitive information, making it the most appropriate choice in this context.