PKI (Public Key Infrastructure)
Public Key Infrastructure (PKI) is the set of roles, policies, hardware, software, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates and manage public-key encryption.
What it means
PKI uses asymmetric cryptography: every entity has a public key (freely shareable) and a private key (kept secret). A document signed with a private key can be verified by anyone with the corresponding public key, proving the signature came from the private key holder. Certificate Authorities are the trust anchors of PKI, vouching that a given public key belongs to a specific entity.
Why it matters for e-signatures
PKI is the cryptographic backbone of advanced and qualified electronic signatures. Understanding PKI helps you evaluate the security claims of any e-signature platform, including SignOwl's use of industry-standard cryptography.
Related terms
Frequently asked questions
Is PKI only used for document signing?
No. PKI is also used for TLS/SSL (website security), code signing, email encryption (S/MIME), and VPN authentication, among many other applications.
What happens to signed documents if a private key is compromised?
If a signing key is compromised, the CA revokes the associated certificate. Documents signed before the compromise date and validated with LTV data embedded at signing time remain valid.
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