The purpose of a reverse proxy is to act as an intermediary server between clients (such as web browsers) and backend servers (such as web servers or application servers). Unlike a forward proxy, which handles requests from clients to access resources on the internet, a reverse proxy manages incoming requests from clients seeking resources hosted on backend servers within a private network or data center. The reverse proxy intercepts client requests and forwards them to the appropriate backend server based on routing rules, load balancing algorithms, or content caching policies. This setup helps improve performance, enhance security, and simplify management of backend infrastructure.
The primary difference between a proxy and a reverse proxy lies in their direction of traffic flow and operational context. A proxy server, also known as a forward proxy, forwards requests from clients to servers on the internet, acting as an intermediary that masks clients’ IP addresses and enhances privacy and anonymity. On the other hand, a reverse proxy sits in front of backend servers, intercepting incoming client requests destined for specific services or applications hosted on those servers. The reverse proxy enhances scalability by distributing client requests across multiple backend servers, improves security by inspecting and filtering incoming traffic, and optimizes performance through caching and compression of responses before forwarding them to clients.
Reverse proxies are utilized in various use cases to optimize, secure, and streamline access to backend services and applications. One common use case is load balancing, where a reverse proxy distributes incoming client requests across multiple backend servers based on predefined algorithms (such as round-robin or least connections). This helps evenly distribute workload and improve overall system performance by preventing any single server from being overwhelmed with requests. Another use case is SSL termination, where a reverse proxy terminates SSL/TLS connections from clients and establishes new connections to backend servers using unencrypted protocols, reducing computational overhead on backend servers and simplifying management of SSL certificates.
Additionally, reverse proxies are employed for content caching to store frequently accessed static content (such as images, scripts, or videos) closer to clients, reducing latency and bandwidth usage. This improves the responsiveness of web applications and enhances user experience by delivering content more quickly. Reverse proxies also play a crucial role in enhancing security by acting as a buffer between clients and backend servers, inspecting and filtering incoming requests to mitigate threats such as DDoS attacks, SQL injection, and cross-site scripting (XSS) attacks. By enforcing security policies and access controls, reverse proxies help protect backend infrastructure from malicious activities while ensuring compliance with regulatory requirements and data privacy standards.