Which Applied Cryptography Solution?

About this interactive

The pattern of this module: identify the problem, choose the cryptography that solves it, build a protocol or system around it. The same few building blocks, hashing, symmetric and asymmetric cryptography and public key infrastructure, turn up in every solution. A VPN tunnel (TLS or IPsec) encrypts traffic between two places across networks you do not trust. A digital signature (a hash signed with the sender's private key) proves a message or document is unchanged and came from its sender. Code signing is the same process applied to a program, with a timestamping authority to keep it valid after the certificate expires. A blockchain chains blocks together by their hashes, so a change to an old record shows up, and a distributed ledger copies that chain across many servers with no central machine. Key escrow hands a key to a trusted third party, to be released only when agreed conditions are met. To sort a card, ask what the need is: private traffic across a network, proof about a document, proof about software, a tamper-evident shared record, or access to a key when something goes wrong.

What you'll learn

Choose the applied cryptography solution that fits a need: a VPN tunnel, a digital signature, code signing, a blockchain or key escrow
Tell apart solutions built from the same parts: a digital signature and code signing are the same hash-and-private-key process applied to a document or to software, and a blockchain chains hashes across a distributed ledger

Aligned to

CompTIA Security+

1.4 Explain the importance of using appropriate cryptographic solutions.

ISC2 CISSP

3.6 Select and determine cryptographic solutions

CompTIA SecurityX

2.3 Given a scenario, implement appropriate cryptographic protocols and algorithms.

2.2 Given a scenario, implement appropriate PKI infrastructure solutions.

NIST 800-53

SC-13 Cryptographic Protection

SC-17 Public Key Infrastructure Certificates

SC-36 Distributed Processing and Storage

ISC2 CC

5.1 Understand data security

Key terms

Virtual Private Network: A technology that creates a secure, encrypted tunnel over a public network to protect data in transit.
Digital Signature: A cryptographic mechanism used to verify the authenticity and integrity of a digital message or document.
Code Signing: The process of applying a digital signature to software using a certificate and private key so that users can verify the authenticity and integrity of downloaded programs.
Blockchain: A chain of data blocks where each block contains a cryptographic hash of the previous block, creating a tamper-evident linked sequence that preserves data integrity.
Key Escrow: A system in which cryptographic keys are stored with a trusted third party and released only when specific conditions are met, ensuring continuity and access management.
Hash Function: A mathematical algorithm that converts input data of any size into a fixed-size output value used to verify data integrity.
Distributed Ledger: A record of transactions or data that is replicated and synchronized across multiple nodes or machines with no single central authority.
Public Key Infrastructure: A framework of hardware, software, policies, and standards used to create, manage, and distribute digital certificates.
Timestamping Authority: A trusted third party that issues cryptographically signed timestamps to prove that a code signature existed and was valid at a specific point in time, preserving trust after a certificate expires.

Topics

Virtual Private Network Digital Signature Code Signing Blockchain Key Escrow Interactive Categorize

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