A reverse proxy is a proxy server that sits before a site's server, and its role is to direct traffic to a specific back-end server. Similar to common forward proxies, reverse proxies act as intermediaries on the server side and provide a variety of important functions for the server. In this article, we will explore the five functions of reverse proxies, revealing its importance in terms of acceleration, security, load balancing, and more.
1. Content caching
A reverse proxy server can store a compressed and cached mirror version of a website's page so that it can be returned directly to the user. This content caching mechanism can significantly improve the user experience by greatly increasing the speed of content delivery based on customer location and minimizing page load times. When users visit a website, the reverse proxy can directly obtain data from the cache, reducing the pressure on the back-end server and improving the overall response speed.
2. Load balancing
The reverse proxy server creates a gateway between the user and the back-end server, so it is able to determine which back-end server to route each HTTP session to. When an application uses multiple back-end servers, reverse proxies can efficiently distribute the load so that requests are evenly distributed across different servers. Especially in the case of high traffic, reverse proxy can avoid the overload of a single server and improve the stability and performance of the overall system. In addition, reverse proxies provide failover solutions that reroute traffic when a back-end server goes offline, guaranteeing the continued availability of a website or service.
3. IP mask
IP masks are an important security measure in reverse proxies, through which all incoming traffic must pass through a proxy server. In this process, the back-end server establishes a connection with the proxy server, and realizes that each user request is resolved by the proxy IP address, thus hiding the real IP address of the back-end server. This simple yet powerful measure plays an important role in reverse proxies, providing a great enhancement to the security of the system.
In the traditional direct connection, the user requests directly reach the back-end server, and the attacker only needs to obtain the real IP address of the back-end server to directly launch attacks against the server, such as DDoS attacks. In DDoS attacks, a large number of fake requests and malicious traffic exceed the processing capacity of the server. As a result, the server cannot respond to requests from legitimate users and thus paralyzes services.
By using the IP mask technology, the real IP address of the back-end server is hidden, and the attacker cannot directly obtain the location of the back-end server, so that the attack against the back-end server cannot be directly launched. The proxy server acts as an intermediary between the user and the back-end server, and the attacker can only see the IP address of the proxy server and cannot determine the location of the back-end server. In this case, even if the attacker launches a DDoS attack, the actual attack is only the proxy server, not the back-end server, thus protecting the security of the back-end server.
IP masks not only protect against DDoS attacks, but also help protect against other types of direct IP attacks, such as port scanning, IP address detection, and malware infections. This makes it more difficult for attackers in cyber attacks, increasing the security of the system.
4. Filter data
The reverse proxy server sits before the site server, so it can effectively filter and clean up all incoming application traffic before it is sent to the back end. In this way, reverse proxies can improve DDoS protection and reduce its impact on back-end servers. In addition, users can improve the security of Web applications by placing a Web application firewall on the reverse proxy to identify and isolate any malicious packets, including hacking requests and bots.
The backend server encrypting and decrypting Secure Socket Layer (SSL) communications for each user can lead to a decrease in efficiency. Reverse proxy servers can help implement efficient encryption for each user. By performing SSL termination on the reverse proxy, the back-end server only needs to process the decrypted data, thus reducing the burden on the back-end server and improving the efficiency of encrypted communication.
To sum up, reverse proxies play an important role in accelerating content delivery, ensuring the security of back-end servers, and achieving load balancing. It provides increased availability, stability and security for websites and services, and is an integral part of modern network architecture. By taking full advantage of the capabilities of reverse proxies, webmasters and developers can improve the user experience, cope with high traffic loads, and strengthen protection against malicious attacks to provide a better Internet experience for users and servers.