Certificates and Trust Models 🔑🔍
X.509 Standard 📜
Overview:
Defines the format of digital certificates.
First issued in 1988, with Version 3 being the current standard.
Includes specifications for a Certificate Revocation List (CRL) to manage invalid certificates.
Fields in an X.509 Certificate:
Version: Indicates the X.509 standard version used.
Serial Number: A unique identifier for the certificate assigned by the Certificate Authority (CA).
Signature Algorithm: Specifies the public key and hashing algorithms used to sign the certificate.
Issuer Name: Details the authority that issued the certificate.
Validity: Contains two subfields:
Not Before: Start date of certificate validity.
Not After: End date of certificate validity.
Subject: Information about the entity to which the certificate was issued.
Subject Public Key Info: Details the public key algorithm and the public key itself.
Certificate Signature Algorithm: Must match the algorithm used in the Subject Public Key Info.
Certificate Signature Value: The digital signature data of the certificate.
Certificate Fingerprints:
Hash digests of the entire certificate, used for validation and inspection.
Web of Trust 🌐🔗
Concept:
An alternative to the centralized PKI model.
Individuals sign each other's public keys rather than relying on a CA.
Involves verifying identities through agreed-upon methods (e.g., ID checks) before signing keys.
Process:
Key Signing Parties: Events where participants verify and sign each other's keys.
Reciprocal Trust: Each party signs the public key of the other, establishing mutual trust.
Web Expansion: As new members are introduced and trusted, they extend the web of trust, linking separate trust networks.
Summary 📈
X.509 certificates provide a structured format for managing digital identities and secure communications.
The web of trust offers a decentralized approach to establishing trust and verifying identities without relying on centralized authorities.
🔐🌍
Last updated