Digital Certificate

Digitally signed electronic document that binds a publuc key with a users identiy

Wildcard certificate - allow for all subdomains to use the same public key cert. can be easy to manage.

if server is compromised and it’s revoked it effects all subdomains.

Subnject alternat name field - cert that specifies what additional domaind and IP addresses are going to be supported.

single-sided certificate - only requires the server to be validated

dual-sided certificate - - requires both server adn user to be validated

self signed certificate - signed by the same entity whose identy it is claimed.

third prty certificates - signed and trused by a trused certificate authority

root of trust - each cert if validated using the root of trust, all sub certs are trusted becuase they are trused on the path.

RA registration authority - requests info and creates the certificate for the user.

CSR - block of coded text recoding the info from the signing authority

crl CERTIFICATE revocation list - list of certs that it has been revoked, normally due to a databreech.

key recovery agent - speceliazed type of software that allows the restoration of corrupted or lost keys.

🔑 Digital Certificates

A digitally signed electronic document that binds a public key to a user, device, or organization’s identity.
Ensures authentication, integrity, and trust.

Wildcard Certificate
- Covers all subdomains of a domain.
- Easier management.
- ⚠️ If revoked/compromised, all subdomains are affected.
Subject Alternative Name (SAN) Certificate
- Lists multiple domains, subdomains, or IPs in one cert.
- Common for organizations with several domains.
Single-Sided Certificate
- Only the server is validated.
- Example: Standard HTTPS website.
Dual-Sided (Mutual) Certificate
- Both server and client validate each other.
- Example: VPNs, high-security enterprise networks.
Self-Signed Certificate
- Signed by the same entity it certifies.
- Not trusted by browsers by default.
- Used in labs or internal testing.
Third-Party (CA-Issued) Certificate
- Signed by a trusted Certificate Authority (CA).
- Widely trusted in browsers and systems.

Root of Trust
- Trust starts with a root CA certificate.
- All subordinate certificates are trusted if the root is trusted.
Registration Authority (RA)
- Verifies user info on behalf of the CA.
- Issues certificates after approval.
Certificate Signing Request (CSR)
- A block of text with organization details and public key.
- Submitted to a CA to request a certificate.
CRL (Certificate Revocation List)
- A list of revoked certificates.
- Typically revoked for compromise, expiration, or policy violations.
Key Recovery Agent (KRA)
- Special tool/service that can restore lost or corrupted keys.

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