Explain the core missions of Information Security?

The core missions of Information Security can be broken down into three main components, often referred to as the CIA triad:

1. Confidentiality: This is about protecting information from being accessed by unauthorized parties. In other words, only those who should have access to something will be the ones who do. This is often ensured through encryption, access controls, etc.

2. Integrity: This ensures that the information is reliable and accurate, and is maintained and updated only by authorized members. This means that the data cannot be modified in an unauthorized or undetected manner. This is often ensured through checksums and hashes.

3. Availability: This ensures that information is accessible to authorized users when they need it. This involves properly maintaining hardware, performing hardware repairs promptly, and keeping systems up to date and patched against known vulnerabilities.

In addition to these, there are other principles like Non-repudiation and Authentication which are also important. Non-repudiation ensures a transaction or an event cannot be denied by a party, and Authentication is about ensuring that users are who they claim to be before granting them access to information.