How does SSL certificate work?
When you are shopping or banking online, you need to make sure, there is HTTPS and a green padlock icon is in the address bar; but the main question is what does HTTPS means? What is significant about that small green padlock?
To answer these two questions, you need to understand SSL certificate and the way it works. Keep reading this post if you want to learn more about these subjects.
Http vs HTTPS
HTTPS is the secure and safe form of HTTP. Actually, it is a protocol used between a browser and a web server. The “S” at the end of HTTPS stands for “secure”. Technically, it refers to HTTP over Secure Sockets Layer or SSL.
HTTPS means all communications between your browser and the web server encoded. SSL certificate plays an important role in building trust between these two. By definition, “an SSL is a web server’s digital certificate, issued by a third party and verifies the identity of the web server and its public key.”
The systematic process of SSL Certificate
It is time to use one example to demonstrate how SSL works. Here is the scenario; imagine you want to connect with a well-known web server and you want all communications with that server encrypted. Therefore, you type in https:// in the bar and then you complete the address. As soon as you hit the enter key the following process will happen:
1. Your browser requests secure pages from the required web server.
2. The web server sends its public key with its SSL certificate, which is digitally signed by a third party; or as we call it “Certificate Authority” or simply CA.
3. Once your browser gets the certificate, it will check the issuer’s digital signature to make sure the certificate is valid. As you know, a digital signature created by a CA’s private key. Your browser, either Chrome or Firefox, previously installed with many major CA’s public keys. Thus, digital signature should verified. Once the certificate’s signature verified, the system would trust digital certificate. A green padlock icon appears in the address bar. The green padlock simply indicates that the web server’s public key really belongs to the web server, not someone else.
4. Now it is time to exchange a secret! Your browser creates one symmetric key or shared secret. It keeps one and gives a copy to the web server. However, your browser does not want to send the shared secret in plain text. Therefore, it uses the web server’s public key to encode and encrypt the secret, and then sends it to the web server.
5. When the web server gets the encrypted symmetric key, it uses its private key to decrypt it. Now the web server gets the browser’s shared key. From now on, all traffic between the client and the web server will encrypt and decrypt with the same symmetric key.
In this example, we actually demonstrate how asymmetric key algorithm and symmetric key algorithm work together.
The Bottom Line
Asymmetric key algorithm is one of the main parts of SSL Certificate helps to verify the identity of the owner. It means that its public key is trustworthy. After the establishment of the connection, symmetric key algorithm or shared key encrypt and decrypt all traffic between two systems.
Keep in mind that HTTPS and green padlock only indicate the decryption of the communications between client and server. It does not mean the website itself is safe and good!
Remember, anyone, including hackers, can launch on-line business and anyone, including hackers can get a SSL certificate for their sites.
Therefore, if you are online shopping you should ensure to use reputable trustworthy and reliable websites.
The source of this article is OperaVPS provider (VPS Hosting), which you can refer to their site and read more.