Secure Sockets Layer or SSL for short is a protocol. It was developed by Netscape for transmitting private documents over internet. SSL uses a cryptographic system which uses two keys to encrypt and decrypt the data. URLs requiring the SSL connection starts with https: instead of http:.
The SSL protocol uses a third party, a Certificate Authority (CA), to identify one end or both end of the transactions. It works in following manner:
The web browser requests a secure page (usually https://).
On receiving the request the web server sends its public key with its certificate.
The browser checks that the certificate was issued by a trusted party (usually a trusted root CA), that the certificate is still valid and that the certificate is related to the site contacted.
The browser then uses the public key, to encrypt a random symmetric encryption key and sends it to the server with the encrypted URL required as well as other encrypted http data.
The web server decrypts the symmetric encryption key using its private key and uses the symmetric key to decrypt the URL and http data.
The web server sends back the requested html document and http data encrypted with the symmetric key.
The browser decrypts the http data and html document using the symmetric key and displays the information.
You can get the SSL Certificate from following authority:
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