In the US, insults are not something for which you can be prosecuted. Calling someone a son of a bitch is not defamatory. No one believes you are really the child of a dog. So that is an opinion. Defamation requires a false factual statement. Truth is a complete defense.
What is Public Key Infrastructure (PKI)? Public Key Infrastructure (PKI) is a set of hardware, software, people, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates. In cryptography, a PKI is an arrangement that binds public keys with respective user identities by means of a certificate authority (CA). Wikipedia.org
A digital signature (not to be confused with a digital certificate) is a mathematical technique used to validate the authenticity... See complete definition. PKI (public key infrastructure). A public key infrastructure (PKI) supports the distribution and identification of public encryption keys, enabling users and ... digital signature (not to be confused with a digital certificate) is a mathematical technique used to validate the authenticity... See complete definition. PKI (public key infrastructure). A public key infrastructure (PKI) supports the distribution and identification of public encryption keys, enabling users and ...