Which port does HTTPS use for secure transmission?

HTTPS, which stands for Hypertext Transfer Protocol Secure, utilizes TCP port 443 for secure data transmission over the internet. This protocol is an extension of HTTP and employs encryption to secure the communication between a user's web browser and the web server. By using port 443, HTTPS ensures that the information transmitted—such as sensitive data, login credentials, and financial transactions—is securely encrypted to prevent eavesdropping or tampering by unauthorized parties.

While HTTP operates over TCP port 80 without encryption, the move to port 443 indicates the use of security protocols, typically TLS (Transport Layer Security) or SSL (Secure Sockets Layer), to establish a secure channel. This distinction is critical for protecting user privacy and maintaining the integrity of the data being sent and received.

The other ports mentioned in the options serve different functions. For instance, TCP port 67 is used for DHCP (Dynamic Host Configuration Protocol), UDP port 123 is used for NTP (Network Time Protocol), and TCP port 53 is used for DNS (Domain Name System). Each of these protocols is essential for network operations but does not pertain to secure web communication like HTTPS does with port 443.