GnuPG

GnuPG (GNU Privacy Guard) is a free software implementation of the OpenPGP standard (RFC 4880). It allows users to encrypt and sign data and communications, featuring a versatile key management system as well as access modules for all kinds of public key directories. GnuPG is a command-line tool with features for easy integration with other applications.

Advantages

• Strong, proven public-key cryptography for encryption and digital signatures
• Free and open-source, ensuring transparency and auditability
• Cross-platform availability (Linux, macOS, Windows)
• Supports various encryption and signing algorithms
• Integrates with many email clients and other applications

Use Cases

• Email encryption
• Digital signatures
• Secure file transfer and verification

Alternatives

• S/MIME (Certificate-based email encryption) (Sovereignty: 3)
• Proprietary PGP implementations (e.g., Symantec) (Sovereignty: 2)

Installation Steps

1. Install GnuPG using your system's package manager (apt, brew, pacman, etc.) or download from gnupg.org
2. Verify installation with 'gpg --version'
3. Generate a new key pair: 'gpg --full-generate-key'
4. Learn basic commands: 'gpg --encrypt', 'gpg --decrypt', 'gpg --sign', 'gpg --verify'
5. Manage keys: 'gpg --list-keys', 'gpg --import', 'gpg --export', 'gpg --send-keys', 'gpg --recv-keys'

Resources

• GnuPG Website
• GnuPG Handbook