Which of the following is a method used for ensuring secure information delivery in the Global Information Grid (GIG)?

Public Key Infrastructure (PKI) is a robust method used for ensuring secure information delivery, particularly in environments like the Global Information Grid (GIG). PKI establishes a framework for creating, managing, distributing, using, storing, and revoking digital certificates, which authenticate the identities of users and systems involved in communication.

The strength of PKI lies in its ability to facilitate secure data exchanges by encrypting information and providing a means of verifying the authenticity of that information through digital signatures. This helps in preserving the integrity and confidentiality of data as it traverses networks, making it essential in military and governmental communications, where security is paramount.

In contrast, conventional mail does not provide the security needed for sensitive information because it lacks encryption and secure identity verification. Regular data backups are vital for data recovery but do not directly secure information during transmission. Manual documentation does not offer any digital security measures and is prone to human error.

This makes PKI an ideal choice for ensuring that information remains secure during delivery within the GIG.