Predict How HTTPS Keys and Certificates Work

About this interactive

From the lesson: - **A key pair:** what one key encrypts, only the other can decrypt. - **Sending a secret:** encrypt with the server's public key, and only the server's private key can decrypt it. - **Proving who you are:** the server signs with its private key, and anyone with its public key can check that it came from the key's holder. - **Certificate authority:** checks that the requester owns the domain, so a browser can trust the server is who it says it is. - **Self-signed:** the traffic is still encrypted, but nobody vouches for the identity, so the browser warns that the site is not secure. - **Why HTTPS everywhere:** without it, someone in between can impersonate even a harmless site and collect what users type. The video calls the two keys "public and private certificates"; they are keys. A certificate holds the public key, the domain, and the CA's signature. HTTPS was first HTTP over SSL; it uses TLS today.

What you'll learn

Predict which key, public or private, encrypts, decrypts, signs and checks in HTTPS
Explain what a certificate authority proves, what a self-signed certificate does not, and why HTTPS on TCP port 443 protects even sites with nothing sensitive

Aligned to

CompTIA Network+

4.1 Explain the importance of basic network security concepts.

1.4 Explain common networking ports, protocols, services, and traffic types.

Cisco CCST Networking

6.2 Describe foundational security concepts

Key terms

Hypertext Transfer Protocol Secure: The encrypted version of HTTP that wraps web traffic in a TLS session, operating on TCP port 443, so that the data exchanged between a browser and a web server is confidential and cannot be read or modified by an eavesdropper. HTTPS is now the standard for all web traffic, indicated by the padlock icon in a browser.
Public Key: A cryptographic key that can be shared openly and is used to encrypt data or verify digital signatures.
Private Key: A secret cryptographic key used in asymmetric encryption to decrypt data or create digital signatures.
Certificate Authority: A trusted entity that issues digital certificates used to verify the identity of individuals, organizations, or devices.
Self-Signed Certificate: A digital certificate signed by the entity that created it rather than a trusted certificate authority, providing encryption without third-party identity verification.
Transport Layer Security: A cryptographic protocol that provides secure communication over a network, successor to SSL.

Topics

Https Tls Public Key Private Key Certificate Authority Interactive Predict

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