Visitors to a company's facilities are connecting to the company's corporate network Wi-Fi and open network ports. Which of the following should the security engineer implement to prevent this unauthorized access?

A Virtual Private Network (VPN) provides a secure connection over the internet, encrypting data between a user's device and the corporate network. However, it does not inherently prevent unauthorized devices from connecting to the network; it merely secures the communication for those already authenticated. Therefore, a VPN alone would not effectively control access for visitors.

WPA3 is a security protocol for wireless networks that enhances encryption and protects against unauthorized access. While it improves the security of Wi-Fi networks, it does not manage or restrict access based on user identity or device compliance, which is crucial in a corporate environment with visitors. Thus, it is insufficient for preventing unauthorized network access.

Host Intrusion Detection Systems (HIDS) monitor and analyze the activity on devices for signs of unauthorized access or malicious behavior. While valuable for detecting breaches, HIDS do not prevent unauthorized access at the network entry point, making them less effective in addressing the immediate issue of visitors connecting to the corporate network.