What is a Proxy Server and How Does it Work?

A proxy server, or proxy for short, is a system or device that acts as an intermediary between
a user’s computer and web servers. It routes internet traffic through itself, thus preventing
direct communication between these two entities. Besides blocking the direct connection
between a computer and web servers, the proxy hides the former’s IP address and instead
associates a new IP address. This way, it anonymizes all outgoing requests by delinking them
from some elements of the user’s identity, particularly their location. This underlying
operation highlights the properties of proxies.

Properties of Proxy Servers

Proxy servers can be used in many ways. However, it is worth noting that these cases are
heavily dependent on the value-generating characteristics of proxies, which include:

• Proxies hide the real IP address and assign a new IP: This way, they not only
  anonymize the requests but also protect the real address from any blocks. As a result,
  they allow users to continue browsing even when the proxy’s IP has been flagged or
  banned. They also prevent CAPTCHA codes. Typically, proxies assign different types of
  IPs, which leads to the existence of various proxy types. For instance, mobile proxies
  assign mobile IP addresses that are affiliated with telecommunication companies.
• Proxy servers isolate the local network from the internet, thus promoting security
  Some proxies have storage capabilities: reverse proxies, for example, can cache
  frequently accessed files.
• Proxies have or utilize processing capabilities: generally, proxies are computers that are
  either configured to act as intermediaries or run proxy software. As such, they have
  processing capabilities, which is why data center proxies are fast and powerful as they
  utilize the resources of high-performance data center proxies.

Types of Proxy Servers

There are different types of proxies, each uniquely satisfying the above properties. These
proxy types include:

1. Residential Proxies

Residential proxies assign residential IP addresses, which belong to land-based internet
service providers (ISP). For this reason, any traffic routed through this proxy type appears to
have been sent by a user who is connected to their home internet. As a result, residential
proxies are not easily blocked.

This proxy type is used for:

• Large-scale web scraping
• Ad verification and brand protection
• Cybersecurity by monitoring websites, testing applications, and identifying threats in
  different locations
• Accessing geo-blocked content
• Social media management
• Accessing sneaker and ticket websites

2. Datacenter Proxies

Datacenter proxies route traffic through powerful data center servers, assigning datacenter IP
addresses. As a result, this proxy type is fast and boasts high performance. However, web
servers usually detect datacenter IP addresses and can sometimes ban them whenever they
detect the slightest bot-like activity.

Datacenter proxies are used for:

• Scraping data from small websites
• Accessing geo-blocked content
• Email protection
• Bypassing geo-blocking
• General web browsing to prevent IP bans and provide online anonymity

3. Mobile Proxies

Mobile proxies route traffic through mobile devices such as smartphones and tablets. As a
result, they associate the requests with the devices’ respective IP addresses, which are
registered by mobile carriers. This proxy type, therefore, offers a greater level of protection
against IP blocking than both residential and datacenter proxies. Oxylabs is here to delve
deeper into mobile proxies.

This proxy type is used for:

• Social media management
• Large-scale web scraping
• Ad verification
• Bypassing geo-restrictions
• Avoiding cookie tracking
• Anonymous web browsing

4. Shared Proxies

Shared proxies assign the same IP address to multiple users simultaneously. For this reason,
they can pose a security risk. However, this also results in extra anonymity because it makes
it harder to trace the origin of specific requests.

5. Private or Dedicated Proxies

Private proxies assign each user a unique IP address. As a result, this proxy type guarantees
privacy.

6. Rotating Proxies

Rotating proxies change the assigned IP address, thereby limiting the number of requests
associated with a single IP. This way, they prevent IP blocking. Rotating proxies are,

therefore, preferred in large-scale web scraping applications or instances where the user
wants to avoid IP bans.

7. Sticky Proxies

Sticky proxies do not change the assigned IP address, meaning all requests will carry the
same IP. This can often lead to IP blocking, especially if the proxy routes an unusual traffic
volume to the same web server.

8. Transparent Proxies

Transparent proxies block direct communication between a computer and a web server
without informing the user that a proxy is in the picture. They are used to restrict access to
certain websites.

9. Forward Proxies

Forward proxies sit in front of the client (browser) and forward requests to the server.
Generally, residential, datacenter, and mobile proxies are examples of forward proxies.

10. Reverse Proxies

Reverse proxies sit in front of the server. They receive requests on behalf of the server. They
are used to store frequently accessed files, offer load balancing, and secure the server
infrastructure by preventing direct communication from the outside.

Final Words

You can achieve a lot using proxies, from web scraping and ad verification to anonymous
browsing and preventing cyberattacks. The utility of proxy servers stems from the fact that
they mask a user’s online identity, isolate the local network from the internet, and have a
certain level of processing power.