A CA certificate can achieve the following functions:
① Identity authentication: The two parties transmitting information in the network can't meet each other, so they can use digital certificates to confirm their identities instead of being impersonated by others.
② Confidentiality of information: The information is encrypted by digital certificate, and only the receiver can read the encrypted information, thus ensuring that the information will not be stolen by others.
③ Integrity of information: Digital certificates can be used to check whether the transmitted information has been tampered with or lost during transmission.
Undeniability: A digital signature with a digital certificate has the same legal effect as a handwritten signature.
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What is the use of CA certification?