PDF glossary
Hardware security module (HSM)
A dedicated device or service that stores private keys and signs with them, without ever letting the keys out.
Organisations that sign at scale, or need their keys protected to a standard, keep them in an HSM or a remote signing service. The application sends what needs signing and receives the signature.
In PDF-SDK
The private key never enters the library: plug in your own signer — an HSM, a remote signing service or a hardware token — and the SDK hands it a SHA-256 digest.
PDF signaturesLast reviewed