Web Scraping Explained By Semalt Expert

Web scraping is simply the process of developing programs, robots, or bots that can extract content, data, and images from websites. While screen scraping can only copy pixels displayed onscreen, web scraping crawls all HTML code with all the data stored in a database. It can then produce a replica of the website somewhere else.

This is why web scraping is now being used in digital businesses that require harvesting of data. Some of the legal uses of web scrapers are:

1. Researchers use it to extract data from social media and forums.

2. Companies use bots to extract prices from competitors' websites for price comparison.

3. Search engine bots crawl sites regularly for the purpose of ranking.

Scraper tools and bots

Web scraping tools are software, applications, and programs that filter through databases and pull out certain data. However, most scrapers are designed to do the following:

  • Extract data from APIs
  • Save extracted data
  • Transform extracted data
  • Identify unique HTML site structures

Since both legitimate and malicious bots serve the same purpose, they are often identical. Here are a few ways to differentiate one from the other.

Legitimate scrapers can be identified with the organization that owns them. For instance, Google bots indicate that they belong to Google in their HTTP header. On the other hand, malicious bots cannot be linked to any organization.

Legitimate bots conform to a site's robot.txt file and do not go beyond the pages they are allowed to scrape. But malicious bots violate operator's instruction and scrape from every web page.

Operators need to invest a lot of resources in servers for them to be able to scrape vast amount of data and also process it. This is why some of them often resort to the use of a botnet. They often infect geographically dispersed systems with the same malware and control them from a central location. This is how they are able to scrape a large amount of data at a much lower cost.

Price scraping

A perpetrator of this kind of malicious scraping uses a botnet from which scraper programs are used to scrape the prices of competitors. Their main aim is to undercut their competitors since lower cost is the most important factors considered by customers. Unfortunately, victims of price scraping will continue to encounter loss of sales, loss of customers, and loss of revenue while perpetrators will continue to enjoy more patronage.

Content Scraping

Content scraping is a large-scale illegal scraping of content from another site. Victims of this kind of theft are usually companies that rely on online product catalogs for their business. Websites that drive their business with digital content are also prone to content scraping. Unfortunately, this attack can be devastating for them.

Web Scraping Protection

It is rather disturbing that the technology adopted by malicious scraping perpetrators has rendered a lot of security measures ineffective. To mitigate the phenomenon, you have to adopt the use of Imperva Incapsula to secure your website. It ensures that all visitors to your site are legitimate.

Here is how Imperva Incapsula works

It starts the verification process with granular inspection of HTML headers. This filtering determines if a visitor is human or a bot and it also determines if the visitor is safe or malicious.

IP reputation can also be used. IP data are collected from attack victims. Visits from any of the IPs will be subjected to further scrutiny.

Behavioral pattern is another method to identify malicious bots. They are the ones that engage in the overwhelming rate of the request and funny browsing patterns. They often make efforts to touch every page of a website in a very short period. Such a pattern is highly suspicious.

Progressive challenges which include cookie support and JavaScript execution can also be used to filter out bots. Most companies resort to the use of Captcha to catch bots trying to impersonate humans.