Shivam Sharma

X.509 defines the format for digital certificates used in TLS, code signing, email encryption, and PKI. Here's what's inside an X.509 certificate, how extensions work, and where format issues cause failures.

Key exchange lets two parties derive a shared secret over an insecure channel without transmitting the secret itself. Here's how DH and ECDHE work, why ephemeral keys provide forward secrecy, and where key exchange fails.

Expired certificates cause more outages than cyberattacks. Here's the real cost of certificate outages, why they keep happening, and the engineering practices that eliminate them.

ECC provides equivalent security to RSA with dramatically smaller keys and faster operations. Here's how elliptic curves work, which curves to use, and why ECC dominates modern TLS deployments.

CMP (RFC 4210/9483) is the most comprehensive certificate management protocol, handling enrollment, renewal, revocation, key update, and cross-certification. Here's how it works, where it's used, and why it's complex but powerful.

Cloud HSMs offer managed key protection without hardware ownership. On-premises HSMs give full physical control. Here's a practical comparison covering security, cost, operations, and decision criteria.

A cryptographic hash function produces a fixed-size fingerprint from any input. Here's how hashing works, why it's irreversible, and where it's used in certificates, signatures, and integrity verification.

Machine identities outnumber human identities 45:1 but are managed with far less rigor. Here's how they differ in lifecycle, scale, and risk — and why treating them the same way fails.

SCEP enables network devices and endpoints to request certificates from a CA using simple HTTP operations. Here's how it works, why it's still everywhere despite being outdated, and where it creates security gaps.

cert-manager automates TLS certificate issuance and renewal in Kubernetes using ACME, Vault, private CAs, and more. Here's how it works, how to configure it, and where it fails silently.