Definition
A proxy server acts as an intermediary, forwarding requests from clients to other servers and returning responses. It sits between users and the internet, intercepting and processing traffic before it reaches its destination. This intermediary role allows for enhanced security, improved performance, and better control over network access. For instance, a proxy can filter malicious content, cache frequently accessed web pages to speed up loading times, or enforce organizational access policies. Unlike a gateway, which typically connects dissimilar networks, a proxy server primarily handles application layer traffic for specific protocols like HTTP. Understanding proxy servers is crucial for network security and administration roles and frequently appears on certifications like CompTIA Security+ and the CISSP exam.