Using an example in the business or finance industry, describe how the following
cryptographic protocols work:
B. Hypertext transport protocol secure
Hypertext Transport Protocol Secure (HTTPS) is a cryptographic protocol widely used in the business and finance industry to secure communication over the internet.
Let's consider the example of online banking. When a user visits their bank's website, they typically enter "https://www.bank.com" in their web browser instead of "http://www.bank.com". The addition of "s" in "https" signifies that the website is using the HTTPS protocol.
Here's how the HTTPS protocol works:
1. Secure Handshake: When a user initiates a connection to the bank's website, their web browser and the server perform a secure handshake. The server presents a digital certificate, which is essentially a document containing the bank's public key and additional information. This certificate is issued by a trusted certificate authority (CA).
2. Certificate Verification: The user's web browser verifies the authenticity of the server's certificate. It checks if the certificate is valid, not expired, and issued by a trusted CA. If the certificate fails any of these checks, the browser displays a warning message to the user.
3. Public Key Exchange: After the certificate is verified, the server and the browser initiate an encrypted connection using a symmetric encryption algorithm. They exchange encrypted data using asymmetric encryption, where the bank's public key encrypts the browser's symmetric key. This ensures that only the server possessing the private key can decrypt the symmetric key.
4. Secure Communication: Once the symmetric encryption key is established, the server and the browser use it to encrypt and decrypt data during the session. This ensures that any information transmitted between them, such as login credentials or financial transactions, is protected from eavesdropping or tampering by attackers.
5. Ongoing Security: Throughout the session, the server and browser continue to encrypt and decrypt data using the shared symmetric key. This ensures the confidentiality and integrity of the data being exchanged. If at any point the connection is compromised or the encryption key is tampered with, the browser and server can detect this and terminate the connection.
In summary, HTTPS ensures secure communication between a user's web browser and a server by encrypting the data exchanged. The protocol uses digital certificates, asymmetric encryption, and symmetric encryption to establish a secure connection and protect sensitive information in the business and finance industry, such as banking transactions.