What is a proxy server?

How does a proxy server actually work? All computers that visit the Internet have different IPs (Internet Protocols). Your IP address is used as your computer's home address. Exactly like when the postal service sends your letters to your home address, the Internet knows how to send the IP address the correct data to the right computer.

When you visit a specific website using a proxy, your computer first sends a site request that goes through the proxy server, and then it sends your request to the website using its IP address. When the website receives the request, it sends the response back through the proxy server, which eventually sends data to your web browser. A proxy is just a computer that has access to the Internet.

When the proxy sends your requests, it can change the data you submit, and you still get the information you expect to see. A proxy can change your IP address, so the web server will not know where you are. It can encrypt the data you send, which makes your data become unreadable. A proxy also can block access to specific web pages based on IP addresses.

There are many reasons people and companies use proxy every day, either in their work-life or free time.

• Improve online security: A proxy server is capable of providing security benefits on top of privacy benefits. You can configure your proxy server to encrypt all connections online to stop hackers and your ISP (internet service providers) from tracking your traffic. You can also prevent having access to known websites with malicious content through the proxy server. It is also possible for companies to connect their proxy server with a VPN, so employees always have internet access through a company proxy. In this way, an employee still has internet access through the company's proxy server. Employees and external users can get direct access to the company's network by using a VPN. When employees use a VPN, the company can confirm and verify that their employees access the right resources such as email and internal data. Besides, it provides a secure encrypted connection to the employees and protects the data against unauthorized access.

• Speeds improvements and bandwidth savings: Organizations can also get better overall network performance with a good proxy server. A proxy can cache (store a copy of the site locally on the web server) accessible pages on the Internet. So when you request the server at https://knowuproxy.com, the proxy then checks to see if it is the latest version of the website and sends you the saved copy then. This means that when many employees hit https://knowuproxy.com from the same proxy server, the proxy server simultaneously sends just one request at a time to https://knowuproxy.com. This will reduce both bandwidth and network performance for the organization.

• Get access to blocked resources: Proxies can also be used to circumvent content restrictions imposed by companies or governments. Some countries hold their citizens in an iron grip and have a keen interest in blocking access to major news media. Activists and journalists can bypass these restrictions by logging into a proxy server on the other side of the earth. When using proxies, it looks like they are in America, but they are in North Korea in reality.

• Privacy benefits: Both companies and individuals use proxy servers to surf the web much more privately. Some proxies can change the IP address, while others can identify the info in web requests. In that way, the destination server can't know who made the request, and this means that the destination server cannot track who made the request; in doing so, it will help hide your info and online habits on the Internet. That way, the proxy server will help keep your private information and browser habits private using the Internet. These advantages are also used by hackers and are the reason why it´s so difficult to discover where the attack originally came from.

• To control Internet usage: Organizations can monitor and control employees' Internet use by setting up a proxy server. Many organizations have strict rules about using the Internet. Which pages their employees may visit during working hours, and therefore can configure the proxy to deny their employee's access to specific web pages. The proxy can also be configured to redirect you to a message on the corporate network notifying you that this is not allowed. It is also possible to monitor employees and log everything on the net, and even if they do not block the web page, they know how long time you are spending surfing the Internet.

Free proxy server

• A free proxy is almost always set up by mistake when it was configured and created. Some have tried to set up a network or set up a proxy server, but they did it wrong, and now their server is an open proxy. There are lots of people scraping the Internet to look for these misconfigured servers. They may do this by using software that scans IP addresses on the Internet for open ports that the proxy server usually uses. Free proxies don't last very long, and they can last anywhere from minutes to hours before they are fixed. Some live longer than others but are usually quickly banned by most search engines and pages and are useless to most people. The majority of free proxies are for illegal purposes, such as hacking and DDOS attacks. There is a high risk associated with making use of the many free services. Making use of the free ones can be extremely risky. Also, those who make their money using ad-based revenue models. Free could be a sign that not enough money has been spent on encryption and hardware. There might also be issues with performance and data security. If you'd like to use a free-of-charge proxy server, you should be very careful. Some of them might be set up to steal your credit card info.

No encryption

• If you are using a proxy server without encryption, it makes no sense to use a proxy server. In case the connection is not encrypted, this means that you send your requests in simple text. Anyone monitoring the connection could see account information, usernames, and passwords. Be sure that no matter what proxy server you use, it encrypts your connection completely.

Browsing history log

• It is also possible that the proxy server logs your web requests and IP address locally without encrypting them. It can be a great idea to determine what data your proxy provider is storing and whether they are saving logs and what law enforcement policy they are following. Are you using the proxy server to stay anonymous? The provider may log and sell your data, and therefore you do not get the expected value for your money.

Transparent Proxy

• A transparent proxy does not hide your IP address and therefore does not give you any anonymity. Transparent proxies are often used to improve network speed and access to websites by saving a copy of the called page, and thus the user has faster access to the content of the page. Companies and schools can also use it to fillet and block access to specific sites such as social media and streaming services; the administrator also can monitor employee or student activity.

Anonymous Proxy

• When your internet connection runs through an anonymous proxy server, it hides your real IP address, but the website you visit will still be able to see that you run through a proxy server. Although it identifies itself as a proxy server, there are still some benefits. It protects your privacy on the web and prevents malicious individuals from stealing your sensitive information, as well as preventing targeted ads based on your location.

High Anonymity Proxy

• Also called an elite proxy, it offers you the highest anonymity and the same benefits as anonymous proxies. It does so by hiding all traces of your real IP address, and thereby the website you visit has no idea that you are using a proxy server. High anonymous proxies like the TOR project make it almost entirely impossible to track where and who you are as your connection goes through several servers. Each has a different IP address.

Distorting Proxy

• Distorting proxy, also called Gateway proxy, is found in one of the middle levels of anonymity. When used, you are able to access web pages while your real identity is hidden; however, it will not hide the fact that you are using a proxy server to visit the website. Using an IP address other than your own protects you from malware and targeted marketing, and at the same time, it can bypass web pages blocked in certain countries, offices, and schools.

Forward Proxy server

• A server between a user or a group of users and the internet and can be configured to filter the internet traffic and provide various services to web users. The term forward proxy refers to the fact that the proxy server sits between the user and the internet, forwards the web request to the internet, and responds to the user. The term "forward" is used to differentiate the Forward Proxy server from the reverse proxy server, which sits between the internet and a server on the internal network.

Reverse Proxy server

• A reverse proxy is a proxy server that retrieves resources on behalf of a client from one or more servers. The client makes requests for resources that are handled by the proxy server. The client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resources, available from a different server. The proxy server then evaluates the request. A reverse proxy is often used to load-balance server requests across multiple servers. They can also help organizations bring down bandwidth load because they act like another server managing incoming requests.

Data Center Proxy

• The term "data center" describes a facility that houses all of these systems and related components, not affiliating with an ISP. Companies use data centers to provide computing services and store information. Google, Facebook, and Amazon are examples of companies that use massive data centers to provide services over the Internet. The proxy exists physically in the data center and is a high-speed and low-priced solution and therefore is used by many to harvest data.

Residential Proxy

• It is installed in your home and uses an IP address provided by an Internet Service Provider. The IP address is tied to a physical device, for example, a mobile phone or desktop computer. Residential proxy servers are different from other proxy servers because they are placed in a location that is not subject to the same inspection level as a commercial proxy server. These servers can increase internet speeds because they are connected directly to the internet rather than through a company's servers. A company will often use these types of servers to increase its own internet speed. Residential proxies are well-suited for social media growth, market research, and retail. They are more trustworthy than example data center proxies that are often associated with spam and are cheaper to acquire than Residential proxies.

Public Proxy

• anyone can use public proxies, and if you do a simple search on Google, you will quickly find thousands of free proxies. There are several reasons why they are free to use; some of them are set up incorrectly when they were made and are now accessible to everyone, while others are set up with malicious intentions, among other things, to intercept personally sensitive information from those who use them. These proxies can be useful if you do not have the money to buy them, but you should always keep in mind that if you use them, they can have certain security consequences. Public proxies are used, among other things, to scrape data and SEO optimization but unfortunately also malicious intentions like hacking, DDoS attacks, and brute-forcing attack. As mentioned early in the article, these proxies do not live long, typically a few hours.

Shared Proxy

• Shared proxies are used by several other people simultaneously and are a cheap solution if you can't afford to buy private proxies. However, there are certain disadvantages associated with using shared proxies. Several others use the same connection; this will also be noticeable on the internet speed, and you may be blamed for other's bad behavior on the net.

SSL Proxy

• An SSL (Secure Socket Layering) proxy is a proxy server that uses the HTTPS (Hypertext Transfer Protocol Secure) protocol to encrypt and decrypt messages. By encrypting all the information being sent to a remote server, SSL proxies prevent third parties from intercepting the messages and viewing the information contained within them. The encryption also helps ensure the identity of the remote server is contacted. Content encrypted on an SSL proxy cannot be cached, so when visiting websites multiple times, you may experience slower performance than you would normally do.

Rotating Proxies

• A rotating proxy can provide multiple IP addresses to each user from a big proxy pool, and the user is assigned a new IP address for every new connection. This means you won't have to change your browser or program settings every time you want a different IP address. It is also possible to rotate the IP address by intervals. These proxies are ideal for web scraping or data mining as you can easily get a new IP every time you get blocked.

Mobile Proxy

• mobile proxies (also called Residential-mobile proxies, 3G, 4G, 5G proxies, LTE Proxies, etc.) are proxies made of SIM (subscriber identity module) cards and modems. They are widely used among many social media growth companies as it is virtually impossible to be IP banned by social media like Instagram or Facebook. The reason why these IP addresses are not just banned is that thousands of people use the same IP addresses through their mobiles, and if they get banned, many people will not be able to access their social media. Mobile proxies can also rotate at specified intervals, thereby gaining a new IP address with each rotation. Mobile proxies have become very popular in the last few years, especially after Instagram's crackdown on bots.

CGI proxy

• A CGI (Common Gateway Interface) proxy is a web page (also called web proxy server) that allows its user to access another website through its IP by entering the websites they want to visit, in most cases anonymously. An anonymous CGI proxy is a proxy server that works through an encrypted web form embedded in another web page hosted securely using SSL.

VPN

• A virtual private network is a secure network that extends across a public network or internet. It enables users to send and receive data across shared or public networks as if their devices were directly connected to the private network. VPNs are handy because they can access region-restricted services such as streaming video and making international phone calls. It protects your data by providing an encrypted connection between your computer, smartphone, or tablet and the internet, which means that your ISP can't tell what you're doing online. It does so by routing all the data from your device through a secure tunnel to a server operated by the VPN provider, which acts as a gateway to the internet. The benefit of this more privacy. It's also good for security. If you're on a public WiFi network or even at a coffee shop, it's much harder for someone to hack or steal your sensitive information.

Proxy vs. VPN

They both act as a middleman; you establish a connection with the proxy or VPN server, and then it forwards your request to the website. It looks like you're connecting from the server for the website, and they don't see anything about your real connection or location.

The significant difference is that it's configured at the system level with a VPN, so all traffic goes through it encrypted and can be used with any app. You can use it while you're, playing a game, streaming music, or file sharing, although most VPN software does allow you to exclude certain apps.

A proxy server is configured at the individual app level, so you would have to go into settings for some software and put in the proxy connection. It would only connect through that software; everything else will be unaffected.

The next significant difference is security. VPNs, in general, are more secure than a proxy; all VPNs pretty much work the same way they're going to encrypt the data and put it in the tunnel, and send it to the server.

As you probably know by now, proxies aren't all the same, there are different types and different protocols that a proxy could use depending on the type of application you're using.

These different protocols offer different levels of security. The first one is HTTP proxy, which can only be used for web content, HTTP is the web protocol, and you're not going to be able to use this with any other type of data.

HTTP

• HTTP proxies are very simple; they offer no extra encryption when connecting to the site; this means that anything you do on the web will be wide open as if you're using it with no proxy connection. The only thing it's doing is hiding your IP address from the website.

HTTPS

• The next type is HTTPS proxy which encrypts everything with the HTTPS protocol. It's very similar to HTTP, except it is encrypted. If you connect to an HTTPS website, it will double encrypted because you're connecting to that website with HTTPS and the server itself uses encryption as well. Like the HTTP protocol, HTTPS only supports web traffic, so you cant use it with anything else.

SOCKS

• The third protocol is SOCKS, and there are 2 versions. socks4 only supports TCP applications and is the old version. Socks5 is the latest version and supports both TCP and UDP applications, SOCKS5  proxy supports any traffic, so if the application supports it, you can use it. In terms of security, the socks protocol does not offer any encryption by itself; you would have to have encryption built into the app connected with whatever service it's using. Many socks proxy servers do have ssh support; it might allow an app to connect with a secure connection, but that's only if the app supports it in the first place.