This section provides a quick introduction of the SSL (Secure Socket Layer) protocol, which provides security protection on data being transferred over the Internet.
What is SSL (Secure Socket Layer)?
SSL is a communication protocol created by Netscape
in 1994 to ensure secure transactions between web servers and browsers.
A good description about SSL was given by Franck Martin
in "SSL Certificates HOWTO" at
http://www.tldp.org/HOWTO/SSL-Certificates-HOWTO:
A browser requests a secure page (usually https://).
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 certificate authority),
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.
The latest version of SSL is version 3.0 which was defined in 1996.
A new protocol called Transport Layer Security (TLS) has been developed
to replace SSL.
