Duke would like to restrict users from accessing a list of prohibited websites while connected...

A URL filter is the most effective control for restricting access to specific websites. URL filtering allows administrators to block access based on domain names, URLs, or content categories such as gambling, social media, or malicious sites.

IP address blocking is less precise because many websites share IP addresses or use dynamic hosting. DLP solutions focus on data protection, not web access control. IPS systems detect and block attacks but are not designed for enforcing acceptable-use browsing policies.

URL filtering is commonly implemented in firewalls, secure web gateways, and proxy servers and is widely used to enforce organizational internet usage policies.