La Cote Saint Andre (1880) - Johan Barthold Jongkind

Deconstructing and Understanding an SSL Certificate

Checking SSL certificates on a browser is easy. Just click the green lock icon and you’re good to go. But what if doing the same in a more hacker way? This is where openssl comes into play. Let’s start by checking the SSL certificate of this website: openssl s_client -connect depth=2 C = US, O = DigiCert Inc, OU =, CN = DigiCert High Assurance EV Root CA depth=1 C = US, O = DigiCert Inc, OU = www....

January 25, 2022 · 8 min · Serhat M. Dündar
Paysage a la Côte Saint-Andre (1886) - Johan Barthold Jongkind

SSL/TLS Handshake, Hybrid Encryption and Public Key Infrastructure (PKI)

Hybrid Encryption: Symmetric and Asymmetric Encryption Combined Both symmetric and asymmetric encryption has advantages and disadvantages. So, which one should we use? Well, nowadays we often use them together. Asymmetric encryption is often used to exchange private keys between parties securely. In other words, parties who would communicate establish an asymmetric encryption protocol in the beginning just to exchange private keys. When the private key exchange is completed, they keep communicating by using symmetric encryption - which is faster than asymmetric encryption....

January 22, 2022 · 6 min · Serhat M. Dündar