CREST Practitioner Security Analyst (CPSA) Practice

What service typically operates on port 443?

1. HTTPS

2. DNS

3. SMTP

4. SNMP

The correct answer is: HTTPS

The service that typically operates on port 443 is HTTPS, which stands for Hypertext Transfer Protocol Secure. This protocol is used for secure communication over a computer network, particularly the Internet. HTTPS provides a secure channel through which data can be transmitted, ensuring that the information exchanged between clients and servers is encrypted and therefore less susceptible to eavesdropping or tampering. Port 443 is specifically designated for HTTPS connections, allowing users to interact with websites securely. When a web browser accesses a website using HTTPS, it establishes a secure connection with the web server using this port, which is paramount in protecting sensitive data such as login information, payment details, and other personal data transmitted during online transactions. In contrast, the other services listed—DNS (Domain Name System), SMTP (Simple Mail Transfer Protocol), and SNMP (Simple Network Management Protocol)—each operate on their designated ports: DNS commonly uses port 53, SMTP uses port 25, and SNMP typically operates on ports 161 and 162. Therefore, these services are not associated with port 443, reinforcing that HTTPS is indeed the correct answer.