The digital certificate is an information security technique that addresses these concerns. It is a standardized mechanism that provides privacy, authentication, integrity, and controlled access to an enterprise's information infrastructure. Public Key Cryptography To fully understand digital certificates, one needs first to understand public key cryptography. Public key-based techniques were invented by Whitfield Diffie and Martin Hellman of Stanford University. The public key is published, while the private key is kept secret, accessible only to the owner.
Encryption is the conversion of a message into an unreadable form.
The keys control both encryption and decryption. For example, if someone encrypts a message or file with an individuals public key, only that individuals private key can decrypt this message. This assures message privacy. Two additional components of information security are integrity and authenticity. If we communicate electronically with those we do not know, we must have a way to address these concerns.