Cryptography and PKI Overview

Cryptographic Solutions

• Cryptography is a crucial method to secure data, communications, and business operations in the digital age.
• Cryptography is constantly evolving, so staying updated on new methods and tools is essential.

Public Key Infrastructure (PKI)

• PKI is a system of hardware, software, policies, and procedures to manage digital certificates.
• PKI is essential for establishing secure encrypted communication channels over the internet.
• PKI handles the creation, management, distribution, use, and revocation of digital certificates.

Public Key

• The public key is shared publicly and used to encrypt data.

Private Key

• The private key is kept secret and used to decrypt data encrypted using its corresponding public key.

Key Escrow

• Sometimes, keys are stored in a third-party repository (key escrow) to protect and recover them.

Encryption

• Encryption changes plain text into unreadable text.
• Different encryption levels (e.g., 128-bit, 256-bit) affect the difficulty of breaking the encryption.

Types of Encryption (Different Levels)

• Full-disk encryption encrypts the entire hard drive.
• Partition encryption encrypts specific disk partitions.
• Volume encryption encrypts a logical volume of files.
• Database encryption encrypts entire databases or sensitive table data.
• Record encryption encrypts individual records within a database.

Asymmetric vs. Symmetric Encryption

• Asymmetric encryption uses two different keys (public and private).
• Symmetric encryption uses the same key for encryption and decryption.

Key Exchange

• Key exchange mechanisms (e.g., Diffie-Hellman, RSA) provide secure key exchange over insecure channels.

Cryptographic Algorithms

• Common algorithms include AES, DES, and RSA.

Key Length

• Key length (in bits) typically correlates with encryption strength.

Hardware Security

• Trusted Platform Module (TPM): A specialized chip storing RSA encryption keys specific to the host.
• Hardware Security Module (HSM): Physical devices safeguarding and handling cryptographic keys.

Data Protection Methods

• Obfuscation, Steganography, Tokenization, and Data Masking: Methods used to hide data or replace it with tokens.
• Hashing: Converts data into fixed-length strings.
• Salting: Adds random data to passwords before hashing to improve security.
• Digital Signatures: Verify the authenticity of digitally signed documents.

Blockchain and Certificates

• Blockchain can function as a secure public ledger for transactions.
• Certificate Authorities (CAs), Certificate Revocation Lists (CRLs), and Online Certificate Status Protocol (OCSP) are components of PKI managing digital certificates.
• Self-signed Certificates: Issued by the entity using them.
• Third-party Certificates: Issued by a trusted third party.
• Root of Trust: The secure starting point for cryptographic or secure boot processes.

Summary

• Cryptography is essential for secure data, transactions, and communications in modern digital environments.
• Various methods and tools exist for diverse security needs.

Key Points

• PKI is fundamental for secure communication.
• Encryption can be applied at multiple levels.
• Hardware security tools (TPM, HSM) enhance security.

Review Questions

• Explain the difference between public and private keys.
• Describe encryption levels and their tradeoffs.
• Describe the role of a Hardware Security Module.
• How does key stretching strengthen passwords?

Practical Exercises

• Setting up a basic encrypted email service.
• Using a steganography tool to hide text within an image.