Forward vs. reverse proxies - What’s the difference?

Written by: Lisa Whelan

When you navigate the internet, your device doesn’t always connect directly to the destination server. Instead, requests are often routed through a proxy before reaching their destination. Proxies come in two primary formats: forward proxies and reverse proxies. A forward proxy sits between the client you’re using (for example, your web browser) and forwards its requests to the internet, while a reverse proxy sits in front of the destination server (for example, the server that holds a website’s data), and handles incoming requests.

Knowing the difference between forward and reverse proxies is key to understanding the broader roles that proxies play in web architecture and security.

Forward-vs.-Reverse-Proxies-1

What is a forward proxy?

A forward proxy is a kind of proxy server that manages requests between a client (for example, your web browser or a mobile application) and the internet. It’s called a “forward” proxy because it takes requests from your device and “forwards” them to the internet. The same way you can receive an email from one email address and forward it to another, a forward proxy acts as a middleman between your device and the internet.

Residential proxies, datacenter proxies, ISP proxies, and mobile proxies are all examples of forward proxies.

What is a forward proxy and how does it work?

Forward proxy use cases

Forward proxies allow computers on a private network to route their traffic through the proxy server before connecting to the public internet. This is useful in cases where people want to add extra control or security to their network traffic. For example, forward proxies can:

  • Hide your IP address by masking it with the proxy server’s IP address
  • Control access to websites by filtering which sites people on the network can visit
  • Monitor network traffic for security or compliance purposes
  • Access geo-restricted or region-specific data

Example

Imagine you run a price comparison company in the travel industry that aggregates prices for airline tickets, hotels, and car rentals. To provide your customers with the best deals, you need to scrape data from hundreds of travel websites. However, the websites you need to scrape often limit the number of requests a single IP can make, or block automated scraping activities altogether. To avoid an IP ban, you need to mask your web scraper’s IP address.

This is where forward proxies come in. Instead of your scraper making direct requests to the travel sites, it can send the requests through a forward proxy – most likely a residential proxy (the best kind of proxy for web scraping). This way, the website only sees the proxy server’s IP address, instead of your real IP.

By using a network of proxy servers, you can rotate between different IP addresses. This ensures that no single IP makes too many requests and triggers an IP ban, so you can continue to scrape the travel websites without interruptions.

What is a reverse proxy?

A reverse proxy is a kind of proxy server that handles requests from clients on behalf of a server (like the requests you send to a website from your web browser). When you visit a website, your request goes through a reverse proxy before it reaches the server that holds the website’s data. Once the website’s server has the information you’ve requested, it sends it back to the reverse proxy, which then delivers it to you.

What is a reverse proxy and how does it work?

Reverse proxy use cases

A reverse proxy lets people access a website by acting as a single entry point. Instead of connecting directly to the website’s servers, you can access the website through the reverse proxy, which enables websites to manage traffic and keep their servers secure. For example, reverse proxies can:

  • Distribute traffic so visits to the website don’t overload any single server
  • Hide the real server for security, so it’s harder for attackers to find and target the actual server
  • Speed up access to the website by serving cached (previously saved) content

Example

Think of a large website like Amazon, that may have millions of people visiting the website at once. A single server wouldn’t be able to handle all the incoming requests, so instead, a reverse proxy sits between the users and Amazon’s network of servers. The reverse proxy distributes the requests efficiently, which makes sure that the traffic doesn’t overload the backend servers. This efficient distribution of traffic helps to maintain the website’s speed and security.

Differences between forward and reverse proxies

The main difference between a forward proxy and a reverse proxy is that a forward proxy acts on behalf of a client to access a server, whereas a reverse proxy works the other way around: it acts on behalf of the server to manage incoming requests from clients.

  • A forward proxy acts as an intermediary for clients (like users or scrapers). It helps clients access the internet by hiding their IP addresses and managing requests to web resources.
  • A reverse proxy acts as an intermediary for servers (like website servers). It manages incoming requests from users, to help with load balancing, security, and caching.

In short, a forward proxy helps clients access resources, while a reverse proxy helps servers manage and protect access to their resources.

Feature

Forward Proxy

Reverse Proxy

Placement

Sits between client and internet

Sits between client and internet

Primary function

Controlling outbound traffic

Managing inbound traffic

Client awareness

Client is typically aware of the proxy

Client is unaware of the proxy

Protocol support

Primarily HTTP, HTTPS, FTP, and SOCKS

HTTP, HTTPS, TCP, UDP, WebSocket, gRPC (depending on implementation)

Benefits

Access control, content filtering, caching, anonymity, IP rotation

Improved security, load balancing, caching, SSL termination

Use cases

Bypassing restrictions, accessing geo-blocked content, avoiding IP bans, bypassing request limits, corporate networks

Web servers, content delivery networks, application servers

Configuration and deployment

Forward and reverse proxies also have very different setup processes. The specific configuration steps for either forward or reverse proxies depends on your chosen proxy solutions and your specific requirements.

Forward proxy setup

Setting up a forward proxy typically involves configuring your browser, application, or device to route its traffic through a proxy server (or a network of proxy servers). You can complete this setup:

  • In your device’s network settings
  • Using your browser or operating system’s built-in proxy configuration tools
  • Using specialized proxy management software (for more advanced configurations or for managing multiple proxy servers)

Reverse proxy setup

To deploy a reverse proxy, you may need to install and configure dedicated hardware and software. The configuration process generally involves:

  • Setting up virtual hosts
  • Defining routing rules to direct traffic to the appropriate backend servers
  • Configuring load balancing algorithms
  • Handling up caching settings
  • Setting up security features

Similarities between forward proxies and reverse proxies

Although forward proxies and reverse proxies fulfill very different roles and have different configurations, there are some similarities between them:

  • Both forward and reverse proxies act as intermediaries that sit between clients and servers
  • They both intercept and process network traffic, allowing for content filtering, caching, and modification
  • Both types of proxies can implement caching mechanisms to locally store content that you access frequently
  • Although they handle different sets of protocols, both forward and reverse proxies deal with HTTP and HTTPS traffic, which are the fundamental protocols for web communications
  • Both forward and reverse proxies can enhance security, albeit in different ways: Forward proxies can provide anonymity and access control, while reverse proxies can hide the origin server, filter malicious traffic, and implement security features like SSL termination
  • Depending on their configuration and implementation, both forward and reverse proxies can play a role in optimizing network performance: Forward proxies can reduce how much bandwidth you use by caching content, while reverse proxies can improve response times by efficiently managing traffic

Use forward proxies with SOAX

If you’re looking to harness proxies for your web scraping projects, you’ll need forward proxies that help you to mask your IP address and automatically rotate, so you can make multiple requests to the same website without triggering rate limits or IP bans. The best kind of forward proxies for this purpose are residential proxies.

SOAX has a huge pool (155 million) of residential proxies that can help you scrape all the data you need, without being interrupted by CAPTCHAs or blocks. You can start using forward proxies with SOAX for just $1.99, which gets you 100MB of traffic to use over three days, so you can get to grips with web scraping for very little investment.

Frequently asked questions

What is the difference between a forward proxy and a reverse proxy?

A forward proxy focuses on helping the client access resources, while a reverse proxy helps the server manage and protect those resources. Here is some more detail:

  • A forward proxy acts as an intermediary on behalf of the client. It sits between your device and the internet, forwarding requests from the client (such as your web browser, or a mobile app) to various servers. You can use forward proxies for anonymity, bypassing restrictions, and accessing geo-blocked content.
  • A reverse proxy, in contrast, acts on behalf of the server. It sits in front of web servers, intercepting requests from clients (for example, requests you make from your web browser) and forwarding them to the appropriate backend server (e.g. the website server that holds the data you want to access). Websites commonly use reverse proxies for load balancing, security, and caching.

What are some examples of forward proxies?

Several types of forward proxies exist, each catering to different needs:  

  • Residential proxies: These use IP addresses from real residential users, offering a high level of anonymity and making them ideal for web scraping and bypassing geo-restrictions.
  • Datacenter proxies: These proxies originate from data centers, providing fast speeds and high anonymity, but they might be more easily detected by websites implementing anti-scraping measures.
  • ISP proxies: These proxies are offered by internet service providers, typically providing decent speeds and anonymity. They are suitable for general browsing and bypassing basic restrictions.
  • Mobile proxies: These use IP addresses associated with mobile devices, offering a unique level of anonymity and access to mobile-specific content.

What is a reverse proxy used for?

Reverse proxies serve various critical functions for web servers and online applications:  

  • Load balancing: They distribute incoming traffic across multiple backend servers, ensuring no single server is overwhelmed and preventing downtime.
  • Security: They can act as a first line of defense, protecting backend servers from direct exposure and potential attacks.
  • Caching: They can store frequently accessed content locally, reducing the load on backend servers and improving response times for users.
  • SSL termination: They can handle SSL/TLS encryption and decryption, offloading this computationally intensive task from backend servers.
  • URL rewriting and redirection: They can modify URLs to provide a cleaner and more user-friendly structure, or to redirect traffic based on specific rules.

Lisa Whelan

Lisa is a content professional, specializing in tech and cybersecurity. She's here to share valuable insights and break down complex technical concepts for the SOAX audience.

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