
SOURCE: Smash Stack
Remote working and web-based services are contributing to the success of many businesses. Yet, dependence on an internet connection makes companies vulnerable to web-based threats. For example, malicious software enters corporate networks when employees browse the internet. Also, clicking and downloading files from anywhere online increases malware risks by 32%. But you can still ban certain websites at work to improve security, and this is where web filtering is useful.
So, what exactly is web filtering, and how does it work? What are its different types, and how can you choose a web filtration tool? You’ll get the answers to all these questions in this article. But first, let’s define the term.
What Is Web Filtering?
Web filtering is the process of restricting which websites a user can access. Web filters look for patterns in text or images and limit objectionable content. Admins can also specify the website or file names they want to block. For example, the admin may tell the web filter to stop executable files. They can also list website names that users shouldn’t visit. A typical example of web filtering is Google’s SafeSearch feature. The feature blocks explicit results from showing up in your search results.
This process helps limit a company’s exposure to malware and phishing attacks. As a result, it’s a valuable solution at an organizational or personal level. But governments may misuse it as a form of social control. For instance, they may block citizens from accessing genuine websites or sharing their opinions.
So, it’s up to the user to add web filtering with positive intentions. The focus should be on network security, not control. In the next section, I’ll look at what happens behind the scenes when you implement it.
How Does Web Filtering Work?

SOURCE: Spiceworks
Web filtering works off a blocked list or permitted list. Thus, the filtering system may:
- Allow access to all websites except the blocked ones
- Limit access to all websites except the permitted ones
When you attempt to access a blocked website, you receive an error message.
Administrators manage the filtering system, allowing them to create a filtered website database. They can also specify restricted websites and content categories. Web filters also use machine learning algorithms to automate the categorization process. They save the business the time of looking through the billions of web pages on the internet.
Companies may add web filtering at various points of the information exchange pathway. Different pathways also distinguish the types of filtering, so let’s talk about this next.
4 Types of Web Filtering
You can add web filtering at various stages of internet communication. For example, you can block content before it reaches the user’s device. Or you can stop it from entering the company’s network itself. Based on this, we have the following 4 types of filtering.
1. Client-Side Filtration
This type of filtration involves installing filter software on the user’s system. Also, you have to configure the software for each device in the company. To this end, client-side filtration is ideal when you want to restrict a few machines. Additionally, you can use it at home or in small companies. This prevents users from accessing distracting websites.
This technique may not be workable in large companies as you must install filter software on each system. The process is long and tedious. That said, users can uninstall the web filtering software to access restricted websites. Administrators must use password protection to prevent users from disabling the software.
2. Server-side Filtration

SOURCE: Business Tech Weekly
You can set up a central server in your network through which every user accesses the internet. You then install the web filter on the central server to centrally manage all filtration rules. Server-side filtering is handy for large companies with many employees.
One advantage of server-side filtration is that the company retains complete control. Administrators can also change access levels for other users. For example, they allow fewer restrictions for more trustworthy employees.
3. ISP-Level Filtration
Here, the internet service provider (ISP) controls web access based on predefined rules. Moreover, businesses and governments may be responsible for setting the rules to guide the ISP.
Like server-side web filtering, ISP filtering affects every user. ISPs may allow companies to filter content based on access levels. That said, companies lose control of filtering customization. This is due to the complex and lengthy task of configuration modification.
4. Search Engine Filtration
This involves restricting the content that users see when they make a search query. Some search engines have this feature pre-built, so users only get results from safe and appropriate websites. For instance, companies use collaboration solutions like Google Workspace or Microsoft 365. Set policies to control what’s shown in each solution when users search the internet. Search engine filtering, by itself, is not enough. To this end, your user can enter the address of an inappropriate website to bypass the filters.
Check out the summary of the 4 different types of web filters below.

Having seen the types of web filtration, let’s now shift our focus to key features you need to look for to select from each type.
3 Important Web Filtering Tool Features

SOURCE: Spiceworks
Web filtration tools are essential to a company’s security strategy. Additionally, they help you restrict access to phishing websites and websites with malware. Moreover, this helps increase productivity by cutting access to inappropriate and distracting content. When deciding on a tool for web filtering websites, you must consider your specific need and use case. Next, you must consider the features offered by these solutions.
1. Scalability
As companies grow, the number of users the web filtration software serves increases. The number of websites, keywords, and users your tool can handle should grow seamlessly with your company. Finally, scaling up your system shouldn’t be expensive for you.
2. Flexibility
Flexibility is an essential feature to consider, especially in large companies. Filter tools should have flexible configurations that allow you to define different access levels for different user groups. Moreover, you should be able to set time-based policies and tweak the customizations to suit different needs. Without flexibility, your filtering tool may become more of a burden than a useful addition.
3. Ease of Maintenance
When choosing a filtering tool, it’s essential to choose one that allows easy maintenance. In this regard, your filtering tool should allow you to easily change access roles and add or remove URLs from the blocked or allowed database. Moreover, it should be easy for you to schedule filter policy updates and enforce these policies across all users. You should be able to download software updates with ease and access schedules reports. Finally, your web filtering tool should also be compatible with the systems already in use within your company. These include your hardware and software systems.
Final Thoughts
Web filtering is indispensable to your company’s network security strategy. It protects your network from malware and phishing attacks. It also gives you control over which websites your employees can access. You can use it to improve employee productivity and focus.
Web filtration tools help you to implement web filtration in your company. You can choose to filter content directly on your user’s devices. You can also add central web filtering at the server or ISP level. Limiting search results is also an option. When choosing a tool, you must look out for scalability, flexibility, and ease of maintenance.
If you want to know more about web filtering, check out the FAQ and Resources sections below!
FAQ
Why is web filtering important?
Web filtering protects a company’s network from malware and phishing attacks. This helps to safekeep confidential data. It also increases employee productivity. It does this by blocking access to distracting or inappropriate websites like social networks or gaming sites. Finally, filtering enables companies to meet regulatory compliance.
What is the difference between web filters and firewalls?
Web filters and conventional firewalls run at various OSI model layers. Firewalls typically operate at layer 3; the network layer. They filter traffic based on IP addresses. Conversely, web filters operate at layer 7; the application layer. Filters identify websites by their URL or domain name, helping to block access to specific websites.
What is proxy web filtering?
Proxy web filtering involves using a proxy server between the client and the web server. This proxy server hides the client’s identity and location. This tricks the web server into believing that the proxy server initiated the request. Companies may use proxy filters to add web filtering. Employees may also use proxy filters to bypass web filtering policies.
Is URL filtering the same as web filtering?
Web filtering is a broader term that covers various techniques to control user access to the web. URL filtering is a subset of web filtering. URL filtering restricts access to websites based on the address you type in the browser address bar. It does this based on predefined URL restrictions. Other types of web filtering include DNS filtering and proxy filtering.
How do I disable web filtering?
You can enable or disable web filtering on your PC with admin permission. To disable it, open your web filtration software and look for settings. You’ll need to enter a password before you can make changes. Find the option to disable web filtering. You may have to uncheck a box or turn off a sliding button.
Resources
TechGenix: Article on Proxy Servers vs Firewalls
Learn the differences between proxy servers and firewalls.
TechGenix: Article on Types of Firewalls
Explore the differences between traditional and cloud-based firewalls.
TechGenix: Article on Cybersecurity Strategy
Find out how to develop the most effective cybersecurity strategies for your company.
TechGenix: Article on Proxy Servers
Read about the key differences between proxy servers and firewalls.
TechGenix: Article on Dealing With InfoSec Threats
Discover infoSec best practices to improve business productivity.