Answer:
Internet sites use public key encryption and certificates to provide security by establishing a secure connection between a client's web browser and the server hosting the website.
Step-by-step explanation:
Internet sites use public key encryption and certificates to provide security by establishing a secure connection between a client's web browser and the server hosting the website. This is done through a process called SSL/TLS (Secure Sockets Layer/Transport Layer Security) encryption.
When a client makes a request to a website, the website responds with its public key, which is used to encrypt the data being sent back to the client. The client's web browser then uses the website's public key to encrypt the data it sends to the website. This ensures that any data being transmitted between the client and the website is secure and cannot be intercepted by a third party.
Certificates are used to authenticate the website and verify that it is legitimate. These certificates are issued by a trusted third-party called a Certificate Authority (CA), and are used to verify the identity of the website's owner. The certificate contains information about the website's owner, the public key that is used for encryption, and the expiration date of the certificate.
When a client visits a website, their web browser checks the certificate to ensure that it has been issued by a trusted CA, and that the domain name on the certificate matches the domain name of the website. If the certificate is valid, the client's web browser establishes a secure connection with the website and any data being transmitted is encrypted using public key encryption.
Overall, public key encryption and certificates provide a secure way for internet sites to transmit data between clients and servers, ensuring that sensitive information is kept confidential and protected from unauthorized access.