What is a Digital Certificate?

by Amrita Mitra | Jul 1, 2020 | CCNA, CCNP, CompTIA, Encryption, Information Security, Security Fundamentals

There are different types of digital certificates. Some most common types of digital certificates are mentioned below.

1. TLS/SSL Server Certificate – A TLS/SSL server certificate is used by a TLS server. When a client wants to establish a TLS connection with a TLS server, the TLS server sends a TLS/SSL server certificate to the client.

2. TLS/SSL Client Certificate – If a TLS server wants to authenticate a TLS client, then the TLS client needs to send its certificate to the server. The TLS client, in that case, uses a TLS/SSL client certificate.

3. Email Certificate – Email certificates are used in the S/MIME protocol. If a user wants to digitally sign or encrypt an email message, the user needs to use an email certificate for that purpose.

4. EMV Certificate – EMV certificates are used by EMV payment cards. This type of certificate is used to validate the authenticity of a payment.

5. Code Signing Certificate – Code signing certificates are used to ensure that a program is not modified during the delivery.

6. Root Certificate – A root certificate is a digital certificate that identifies the root CA. What is a root CA?

I hope this helps. However, readers who want to know more about cryptography and Public Key Infrastructure can refer to the book Cryptography and Public Key Infrastructure.

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