How is the public key distributed in an orderly, controlled fashion so that the users...

A digital certificate, issued by a trusted Certificate Authority (CA), binds a public key to the identity of an entity (e.g., user, organization). This provides a means to validate ownership of the public key.

CEH v13 Reference:

Module 17: Cryptography

"A digital certificate ensures the authenticity of the public key through a trusted third party known as a Certificate Authority."

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