What Is SSL?
SSL is a security protocol. For establishing an encrypted link between a website (server) and a browser(client), there should be a standard security technology. SSL (Secure Sockets Layer) provide that slandered technology.
Sensitive information such as credit card numbers, social security numbers, and login credentials can be transmit securely with SSL. Normally, data sent between browsers and web servers is sent in plain text—leaving you vulnerable to eavesdropping. If an attacker is able to intercept all data being sent between a browser and a web server they can see and use that information.
SSL protocol state few parameters to be share between server and client for verify the server and encrypt the sessions. All browsers have the capability to interact with secured web servers using the SSL protocol. However, the browser and the server need what is called an SSL Certificate to be able to establish a secure connection.
What is an SSL Certificate and How Does it Work?
SSL Certificates have a key pair: a public and a private key. Using this two keys it can establish an encrypted connection. The certificate also contains what is called the “subject,” which is the identity of the certificate/website owner.
To get a certificate, you must create a Certificate Signing Request (CSR) on your server. This CSR creates the private key and a CSR data file that you send to the SSL Certificate issuer (called a Certificate Authority or CA). The CA uses the CSR data file to create a public key to match your private key without compromising the key itself. The CA never sees the private key.
Once you receive the SSL Certificate, you install it on your server. You also install a pair of intermediate certificates that establish the credibility of your SSL Certificate by tying it to your CA’s root certificate. The instructions for installing and testing your certificate will be different depending on your server.
1.Browser connects to a web server (website) secured with SSL (https). Browser requests that the server identify itself.
2.Server sends a copy of its SSL Certificate, including the server’s public key.
3.Browser checks the certificate root against a list of trusted CAs and that the certificate is unexpired, unrevoked, and that its common name is valid for the website that it is connecting to. If the browser trusts the certificate, it creates, encrypts, and sends back a symmetric session key using the server’s public key.
4.Server decrypts the symmetric session key using its private key and sends back an acknowledgement encrypted with the session key to start the encrypted session.
5.Server and Browser now encrypt all transmitted data with the session key.
Why Do I Need SSL?
One of the most important components of online business is creating a trusted environment where potential customers feel confident in making purchases. Browsers give visual cues, such as a lock icon or a green bar, to help visitors know when their connection is secured.
In the below image, you can see the green address bar that comes with extended validation (EV) SSL Certificates.