Key generation

As explained in Real-World Cryptography

An algorithm that generates cryptographic key material, such as a public-key and private-key pair.

A key generation algorithm creates cryptographic key material before communication begins. In asymmetric encryption, it produces a public key that may be shared and a private key that must remain secret; a security parameter controls key strength. section 6.1

A typical key-generation role looks like this:

• Choose a security parameter, usually indicating the desired key size or security level. section 6.1
• Generate a related public/private key pair. section 6.1 section 7.1
• Publish or exchange the public key while protecting the private key. section 6.1 section 5.1
• Use the resulting pair for encryption and decryption, signatures and verification, or shared-secret derivation. section 6.1 section 7.1 section 5.1

Alice and Bob establish a secret

Alice and Bob each generate a key pair, exchange public keys, and combine the peer's public key with their own private key. Both obtain the same shared secret, while a passive observer cannot reproduce it. Without authentication, however, an active man-in-the-middle can impersonate both parties. section 5.1

Figure 6.2 To use asymmetric encryption, you first need to generate a key pair. Depending on the security parameters you provide, you can generate keys of different security strengths.

Shows how the chosen security parameter affects the generated key pair's security strength. section 6.1

How Real-World Cryptography covers it

How deep it goes

Defines inputs and outputs and shows protocol roles, but defers concrete generation algorithms and implementation details.

Examples

Uses Alice-and-Bob encryption, signature, and key-exchange scenarios, including passive observation and active man-in-the-middle attacks.

What it assumes

Assumes basic encryption concepts while building the public/private-key distinction from the problem of sharing one secret with everyone.

What you can do after

Evaluate how a cryptographic protocol creates, shares, and uses related public and private keys.

How it connects

Connects public keys, private keys, asymmetric encryption, digital signatures, key exchange, shared secrets, and security parameters.

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Related concepts

• public-private key pairproduces · A public-private key pair is a mathematically related public key and private key used together for asymmetric cryptographic operations.
• digital signaturepart of · A digital signature is cryptographic data generated with a private key and verified with corresponding public information to authenticate data or its signer and detect alteration.
• public keyproduces · A public key is the openly distributable component of an asymmetric cryptographic key pair, used for encryption, authentication, or signature verification.
• private keyproduces · A private key is the secret component of an asymmetric cryptographic key pair used by its holder for operations such as authentication, decryption, or digital signing.
• cryptographic algorithmuses · A cryptographic algorithm is a mathematical procedure that transforms data or generates cryptographic values to provide security properties such as confidentiality, integrity, or authentication.

This explainer was generated by Manning's knowledge graph from the text of Real-World Cryptography. The section links point to the parts of the book it draws on.