How are Server side SSL Certificates validated by browsers?

Public key certificates are digital certificates to prove the ownership of a public key. Certificates are typically signed by a certificate authority (CA). Upon receipt of the cert from a site, CA will sign the cert, saying the public key in the cert is tied to the domain or the ip address of the site. CA will then send the cert to the site. When you access a secured website from your browser, let us say https://www.google.com, your browser will establish a secure communication channel. It will ask for a certificate from the site. The site will share its certificate signed by a trusted certificate authority. The browser has all the list of public keys of the major certificate authorities. This way the browser easily verifies the signed certificate using the public key of the certificate authority who signed the certificate. If the certificate is valid, Browser will generate a symmetric key that will be used to encrypt the communication traffic. Browser will then encrypt the symmetric key using the public key from the site's certificate and send the ciphertext to the site. Only the site can decrypt the ciphertext since it possesses the private key associated with its certificate. The symmetric key decrypted from the ciphertext will be then used for encryption and decryption of messages between the two parties.

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