Learn in the textbookAdvanced Threat Protection and Network Architecture / Communication Security
DefinitionSSL/TLS is a protocol that encrypts communication, for example between a browser and a web server, and uses a server certificate (サーバ証明書) to confirm that the server on the other end is genuine.
ExplanationA server certificate is an electronic certificate in which a trusted third party, a certificate authority, vouches for who owns the server. On the web, HTTP communication over SSL/TLS is called HTTPS, and its URLs begin with https://. SSL is the older predecessor and today its improved successor TLS is used, but the two are commonly referred to together as SSL/TLS.
AnalogyIt is like checking the other person's ID and then exchanging letters in envelopes no one can see through. Whoever handles them along the way cannot read what is inside.
Memory hookThe final s in https stands for secure. If the s is there, the communication is protected by SSL/TLS.