A complete guide to using proxy servers for web parsing

All you need to know when choosing proxies for a project! If you ever seriously parsed, you quickly realized that proxies are one of the key components of any web parsing. In a parsing project with serious amounts of data, a proxy server is not a recommendation, but a necessity. Nevertheless, sometimes it takes more time to configure and fix problems that arise with the server than to create and maintain the parsers themselves. In this guide, we will analyze the differences between the main proxy settings and give you information that you need to consider when choosing a proxy server for a project or business.

What is a proxy server and why are they needed when parsing?

Before talking about proxies, we first need to understand what IP addresses are and how they work. An IP address is a set of numbers that is assigned to any device connected to the Internet Protocol, such as the Internet, which gives each device a unique identifier. Most IP addresses look like this:

A proxy is an intermediary server that routes your traffic through itself and replaces your IP address with your own. When you send a request to a site through a proxy, the site does not see your IP, it only sees the IP address of the proxy server, which allows you to anonymously view (or parse) web pages. Now the whole world is gradually moving from the IPv4 standard to the new IPv6 standard. The new version of the protocol allows you to create more IP addresses. However, IPv6 is not so important in the proxy business, so most IP addresses still use the IPv4 standard.

When parsing a website through a proxy, it is recommended (but rarely in practice) to indicate the name of your company as a user agent so that the website owner can contact you if your parser is overloading their server or if it is not wants you to parse data from his site.

There are a number of reasons why it is important to use proxies when parsing:

  • A proxy (especially a pool of proxy servers – more on that later) allows you to scan a website much more reliably, significantly reducing the likelihood that your scanner will be banned or blocked.
  • Using a proxy, you can send requests from a specific geographic region or device (for example, from mobile IP addresses), which allows you to view the specific content displayed on the website for a given location or device. This is of great importance when collecting data on products in online stores.
  • Using a pool of proxy servers, you can, without fear of blocking, send more requests to the target website.
  • A proxy server allows you to bypass the general IP prohibitions imposed by some websites. Example: websites often block requests from AWS, as there is information that some attackers overload websites with large volumes of requests using servers from Amazon.
  • By connecting through a proxy server, you can conduct an unlimited number of simultaneous sessions on the same or different sites.

Why use a proxy pool?

Well, we figured out what proxies are, but how to use them when parsing?

If you use only one proxy server during parsing, then this is the same as if you used only your own IP address for parsing – this will reduce your scanning reliability, geo-targeting settings and the number of simultaneous requests that you can make.
As a result, you need to create a pool of proxy servers through which you can forward your requests. Thus, you will distribute traffic to a large number of proxies.

The size of your proxy pool will depend on a number of factors:

  • The number of requests per hour.
  • Target websites – Larger websites with more sophisticated anti-bot measures will require a larger proxy pool.
  • The type of IP address you use as proxy server: data center, home or mobile IP address.
  • Is the quality of the IP addresses you use as proxies public proxies, public or private dedicated proxies? Are they data centers, residential or mobile IP addresses? (Data center IP addresses are generally of lower quality than IP addresses for home and mobile devices, but they are often more stable than IP addresses for residential / mobile systems due to the nature of the network).
  • The complexity of your proxy management system is proxy rotation, traffic regulation, session management, etc.

All of these five factors have a big impact on the performance of your proxy pool. If you incorrectly configured the proxy server pool for your project, then with a high probability you will find that your proxy servers are blocked and you can no longer access the target website.
In the next section, we will look at the different types of IP addresses that you can use as a proxy.

What are the proxy options?

If you have studied at least a bit of the existing proxy server options, you probably realized that this was a very confusing topic. Each proxy service developer publicly declares that he has the best proxy IPs on the entire Internet, but few explain why this is so. Because of this, it is difficult to determine which proxy service is the best for your particular project.

  • IP data centers . Data Center IP Addresses – The most common type of proxy IP. These are the IP addresses of servers located in data centers. Such IP addresses are the most common and cheapest to buy. With the right choice of proxies, you can build a reliable parser for your business.
  • Resident IP . Resident IPs are the IP addresses of private homes that allow you to direct your requests through the “home network”. Such IP addresses are more difficult to obtain, which makes them significantly more expensive than server ones. In most cases, server IP addresses do the job. Using resident IPs automatically raises legal issues / consent issues due to the fact that you are using a personal network of people for parsing.
  • Mobile IP . Mobile IPs are the IP addresses of private mobile devices. As you can guess, getting the IP addresses of mobile devices is quite difficult, which makes them the most expensive on our list. For most web parsing projects, mobile IP addresses are redundant unless you want to analyze the results shown to users of mobile devices. But the most important thing is that they raise even more complex legal / resolution issues, as often the owner of the device does not fully realize that you are using their GSM network for parsing.

Public, shared or dedicated proxies?

Another question worth discussing is which proxies to use: public, general or dedicated?

From public (or so-called “open”) proxies, you should stay away. Such proxies have poor connection quality and can be a real danger to you. These proxies are open for free connection, therefore a large number of dubious requests go through them, which inevitably leads to blacklisting and blocking on sites. The worst part about them is that these proxies are often infected with malware. If you have not configured your security properly (using SSL certificates, etc.), then using a public proxy server, you run the risk of spreading existing malware, infecting your own computers and even publicizing your parsing of sites.

Choosing between shared or dedicated proxies is a bit trickier. Depending on the size of your project, your performance needs and budget, a paid subscription to access a common pool of IP addresses may be sufficient. However, if your budget allows and performance is important, then it’s better to pay for a dedicated proxy pool.

So, now you have a good idea of ​​what proxies are and what are the pros and cons of different types of proxy server IP addresses. But choosing the right proxy server is the tip of the iceberg, the most difficult task is managing pro

How to manage your proxy pool?

If you plan to parse on an industrial scale in the long term, it is not enough just to buy a pool of proxy IP addresses and route your site requests through them. Your proxies will inevitably be blocked and stop returning high-quality data.

So what awaits you:

  • Blocking detection – your proxy service should be able to detect numerous types of inhibitions in order to be able to identify and fix the main problem in a timely manner – for example: captcha, redirection, blocking, hosting (complete stop of communication from the server side), etc.
    Repeated requests – if your proxy servers encounter errors, locks, timeouts, etc., they should be able to repeat the request through other proxies.
  • User Agent – managing this metric is critical to successful parsing.
  • Management of a proxy server – sometimes when parsing it is required that you conduct a connection session through the same proxy server, for this you need to additionally configure your proxy pool.
  • Add delays – to hide the fact of parsing, randomize delays when sending requests and “clicks”.
  • Geo-targeting – sometimes you need to configure the pool so that certain proxies are used for certain sites.

Managing a pool of 5-10 proxies is easy, but if you have 100 or 1000 proxies, then the entire network can quickly fall apart. To avoid such problems, you have three main solutions: Do-it-yourself, Proxy Rotators and Everything for You.

Do it yourself

In this case, you purchase a pool of shared or dedicated proxy servers, and then you create and configure a proxy server management solution yourself to overcome all the problems that arise. On the one hand, this is most likely the cheapest option, but, on the other hand, it can be the most expensive in terms of resources and time. This option is suitable for you if you already have a parsing team with enough bandwidth to manage the proxy server or if you have a small budget and you cannot afford anything better.

Proxy rotation

The best solution is to buy a proxy from a provider that provides address rotation and geo-targeting. In this case, you will be spared the solution to the basic problems of pool management. You will be able to devote more time to developing and configuring session management, adjusting bandwidth, identifying ban reasons, etc.

Everything is for you

The final decision is to completely outsource the proxy server management. Solutions like Crawlera are designed as smart loaders, where your parsers simply request its API and it will return the necessary data to you. Managing all the functions of rotation, adjusting, processing blacklists, managing sessions, etc. – you will not need to be distracted by this.

Each of these options has its pros and cons, so choosing the best solution will depend on your specific priorities and limitations.