What is a Proxy Server?

Proxy servers come in various types, each designed to serve specific needs and use cases. Understanding the differences between these types is essential for choosing the right proxy for your requirements.

Reverse Proxy – A reverse proxy acts on behalf of a server rather than a client. It directs incoming requests from the internet to a specific server, helping to balance load and improve security. In the debate of proxy vs. reverse proxy, the reverse proxy is unique in that it hides the server’s identity from the outside world. A reverse proxy may also act as the following:

• Web Application Firewall (WAF): A reverse proxy can function as a WAF by inspecting incoming traffic for malicious activity and filtering out harmful requests before they reach the server. It acts as a shield, blocking attacks like SQL injections and cross-site scripting (XSS), thereby enhancing the security of web applications.
• Content Distribution Network (CDN): A reverse proxy can act as a CDN by caching content closer to users, reducing latency, and speeding up content delivery. It distributes traffic across multiple servers, balancing loads and ensuring high availability, while minimizing the distance data travels to reach end-users for faster access.
• Load Balancer: A reverse proxy acts as a load balancer by distributing incoming client requests across multiple servers, optimizing resource use, and preventing any single server from becoming overwhelmed. This improves overall performance, reliability, and ensures continuous availability by dynamically directing traffic to the most responsive and least loaded servers.

SSE Proxy – Security Service Edge (SSE) acts as a proxy by providing secure, cloud-based access to internet resources and applications. It intermediates user traffic, applying security controls such as data loss prevention (DLP), threat protection, and secure web gateways (SWG). SSE ensures that all traffic is inspected, encrypted, and monitored, effectively safeguarding against cyber threats and ensuring compliance with security policies across remote and distributed networks.

Forward Proxy – A forward proxy is the most common type, acting on behalf of the client to access the internet. It masks the client’s IP address, providing anonymity and the ability to bypass geo-restrictions. Forward proxy servers are often used for content filtering and monitoring.

SSL/TLS Proxy – An SSL/TLS proxy facilitates the inspection and filtering of encrypted traffic. By decrypting SSL (Secure Sockets Layer) or TLS (Transport Layer Security) traffic, it ensures that potentially harmful content doesn’t bypass security checks. SSL proxies are vital for organizations requiring deep packet inspection without compromising security.

Open Proxy/Public Proxy – A public web proxy, also known as an open proxy, is available to any internet user. While these proxies provide anonymity, they often lack security and can expose users to risks. Public proxies are generally free but come with the caveat of slower speeds and potential security vulnerabilities.

Transparent Proxy – A transparent proxy server does not modify the request or response and typically operates without user awareness. It is often used for content filtering and caching but does not offer anonymity since the original IP address remains visible. Transparent proxies are common in corporate networks.

Anonymous Proxy – An anonymous proxy hides the user’s IP address but reveals that the user is using a proxy. This type of proxy offers privacy without the user’s identity being exposed to the websites they visit, making it a common choice for general privacy concerns.

High Anonymity Proxy – High anonymity proxies, also known as elite proxies, provide the highest level of privacy by not only masking the user’s IP address but also concealing the fact that a proxy is being used. These proxies are ideal for activities requiring maximum security and anonymity.

Shared Proxy – A shared proxy is used by multiple users simultaneously, which can reduce the cost but may also impact speed and performance. While shared proxies are cost-effective, they are less secure and can result in slower connection speeds compared to dedicated proxies.

Distorting Proxy – A distorting proxy modifies the user’s IP address by replacing it with a fake one, while still identifying itself as a proxy server. This type of proxy is useful for bypassing geo-restrictions while maintaining a level of anonymity.

Data Center Proxy – Data center proxies are not affiliated with an internet service provider (ISP) and are instead provided by data centers. These proxies offer high speed and are often used for activities like web scraping, but they can be easily detected and blocked by websites.

Residential Proxy – A residential proxy routes your traffic through IP addresses provided by ISPs, making it appear as though the request is coming from a regular residential user. This type of proxy is less likely to be blocked by websites and is ideal for accessing geo-restricted content.

Rotating Proxy – A rotating proxy server automatically switches between different IP addresses at set intervals or for each request. This is especially useful for web scraping or activities that require multiple requests to avoid detection and blocking. Rotating proxies enhance anonymity and reduce the risk of being blacklisted.