What is a Proxy server? Learn about its role in internet security and privacy

Proxy servers are systems or applications that serve as an intermediary between a client and web servers online. They are designed to enhance security by providing an additional layer of protection against cyberattacks or to obscure the user's IP address when accessing the internet from a private network.

How a Proxy server works?

A proxy server functions as a computer with its own IP address that intercepts client requests and forwards them to web servers. Once the web server responds with the requested web page, the proxy delivers it back to the user's web browser.

Users can set up a proxy server by purchasing or installing gateway software on their computer, device, or network. Configuring the server involves specific steps depending on the operating system and type of server used.

Many organizations utilize proxy servers to encrypt traffic, preventing interception by third parties during transmission, and to allow employees to bypass geographical content restrictions and filters that may impede web scraping activities.

In addition, proxies are employed to monitor and manage online activities within workplaces by intercepting requests and blocking access to prohibited websites or IP addresses.

Types of Proxy servers

Proxy servers come in various types, including forward, transparent, anonymous, reverse proxies, and more, each serving specific purposes. Here’s a breakdown of some common types:

Forward Proxy

A forward proxy stands between a user’s device and the internet, inspecting traffic as it passes through. It evaluates requests based on predefined policies, deciding whether to permit or block access to certain websites or IP addresses. For instance, it can prevent users from accessing banned sites in their web browsers.

Transparent Proxy

Transparent proxies, also known as intercepting proxies, intercept user traffic without modifying requests to web servers. They are often used by companies to monitor user activity or by administrators in public Wi-Fi networks to block inappropriate content at locations like airports and hotels.

It’s worth noting that transparent proxies can be installed without requiring any configuration on end-user devices, making their presence less detectable by users.

Anonymous Proxy

Anonymous proxies, also known as hidden proxies or anonymizers, intercept user requests, masking their original IP address and substituting it with a new one. This process conceals the user's IP and location from the target web server.

However, these proxies typically disclose to the web server that the connection is made through a proxy via an HTTP header.

Anonymous proxies offer users a convenient way to bypass regional content restrictions or shield their IP addresses from third-party websites. It's important to note that revealing the use of an anonymous proxy to a web server may prompt the server to block the connection.

There are different levels of anonymity provided by anonymous proxies:

• Level 1: Elite Proxies – Offer the highest level of anonymity by hiding the device's IP address and not indicating the use of a proxy.
• Level 2: Anonymous Proxies – Hide the IP address but notify the web server that the user is using a proxy via the Via header.
• Level 3: Transparent Proxies – Provide no anonymity as they reveal both the user's IP address and the proxy server's IP in their requests.

Reverse Proxy

A reverse proxy is positioned in front of a web server to intercept client requests before they reach the server. Unlike forward proxies that act on behalf of clients, reverse proxies serve the web server by handling requests from end users.

Companies often use reverse proxies to enhance security by shielding public-facing web servers from direct access, reducing vulnerability to DDoS attacks. They can also optimize website performance through load balancing, distributing incoming traffic across multiple servers.

Distorting Proxy

A distorting proxy server operates between a client and a web server, intercepting user requests to websites and altering the HTTP header to modify the client's IP address before forwarding it to the target server.

Distorting proxies aim to deceive web servers by providing a falsified IP address for the client, enabling users to bypass content restrictions and preventing the web server from monitoring browsing activity.

It's important to note that while distorting proxies can be detected and blocked, they are generally more challenging to identify compared to other proxy types.

Data center Proxy

A data center proxy is positioned between a client and a web server, intercepting user requests and replacing their IP address with one associated with a physical data center.

A defining characteristic of data center proxies is that the IP addresses used to mask clients originate from data centers provided by companies such as Bright Data and Oxylabs. These providers allow organizations to lease multiple IP addresses simultaneously.

Businesses often use data center proxies for scenarios requiring secure online identities, particularly during resource-intensive tasks like web scraping, while maintaining high performance and minimal latency.

Residential Proxy

Residential proxies function between a client and a web server, substituting the user's IP address in requests with a physical IP address sourced from a pool of proxies tied to an Internet Service Provider (ISP).

These proxies are linked to physical locations, making them more challenging for websites to detect and block.

Organizations commonly utilize residential proxies for conducting competitive market research due to their stealth capabilities and difficulty in detection.

Public Proxy

A public proxy, also known as a shared proxy, is a type of proxy server accessible online for anyone to use. Users can find public proxies via search engines and share IP addresses with other global users.

While convenient and often low-cost or free, public proxies have drawbacks. Servers can track and log user activities, posing potential security risks such as malware infection. Additionally, simultaneous usage by multiple users can consume bandwidth, potentially reducing performance for individual users.

SSL Proxy

An SSL proxy serves as a transparent proxy server intercepting requests from clients to web servers, encrypting or decrypting them using Secure Sockets Layer (SSL) encryption.

These proxies enhance security by protecting data transmitted between clients and servers, minimizing the risk of eavesdropping on user activities. SSL proxies can also decrypt encrypted traffic, inspect it against content filters, and decide whether to block or allow it accordingly.

Advantages of using a Proxy server

Deploying a proxy server on a private network offers several benefits:

• Security and anonymity: The proxy server acts as a buffer between your network and the internet, preventing destination servers from identifying your device's physical IP address when accessing websites.
• Bypassing regional restrictions: By changing your IP address through a proxy, you can circumvent geographical content limitations and access restricted content.
• Content filtering: Proxy servers enable monitoring of user activity and can block access to inappropriate websites or blacklisted IP addresses.
• Network efficiency: Proxy servers can cache pages from frequently visited websites. This allows users on the network to access web pages via the proxy server without initiating requests to the web server each time, thereby optimizing network performance and bandwidth usage.

In conclusion, employing a proxy server can safeguard your online anonymity, bypass content restrictions, and facilitate content filtering to manage employees' web access effectively.