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What is Web Filtering?

We can all agree that allowing our most valuable treasure, our children, to walk freely on a haunted street is quite risky. This holds true in the digital world as well. Our children and teenagers may expose themselves to perils in the virtual world, which has grown more hazardous than the real world.

Of course, no one is opposed to their unrestricted exploration of the world, but keeping kids out of dangerous areas is one of our most critical responsibilities as adults if their safety is at issue.

When it comes to providing security in the internet world, one of the first techniques that come to mind as a solution will be the filtering of web content.

The term "Web filtering" means managing users' web access by allowing them to choose which websites they may visit, what information they can view, and which things they can download.

This article will provide an overview of web content filtering solutions, define the various content filtering methods, and underline the necessity of blocking certain websites.

What are Web Filtering Types?

A web filtering service can function in a number of ways. One way web filtering solutions might be distinguished is by how they define permitted material. There are several techniques to define web filters, including:

  1. Keyword And Content Filters
  2. Blocklist & Allow List Filters
  3. Browser-based Filters
  4. Client-side Filters
  5. Network-based Filters
  6. Search Engine Filters

1. Keyword And Content Filters

Based on the content of a webpage, content and keyword filtering determines whether to allow or ban traffic. For instance, a company may set filters in place to prevent visitors from accessing sites with adult content. When a request is made, the site's content is reviewed, and if the policy is broken, the site is banned. This filtering method enables an organization to prevent harmful or unsuitable websites that it is unaware of.

2. Blocklist & Allow List Filters

Allow lists are used to indicate which websites a person, system, or program is allowed to access. All web traffic is verified against this list, and any requests with a destination that is not on the list are rejected. This allows for very precise control over which sites can be viewed.

Blocklists are the complete opposite of allowing lists technique. Instead of identifying which sites a user may browse, they state which sites should not be viewed. A blocklist inspects all traffic and drops any traffic to a site on the list. This method is frequently used to guard against known-bad places such as phishing sites, drive-by virus downloads, and unsuitable material.

3. Browser-based Filters

Browser-based filtering services such as web filters are typically extensions, applications, or add-ons that can be implemented and used with a specific internet browser.

Browser-based filtering services such as web filters are typically extensions, applications, or add-ons that can be implemented and used with a specific internet browser.

While not the most web-based filter option, these types of web filters are commonly available and quite simple for consumers.

There are many extensions available for Google Chrome and Mozilla Firefox that blocks pre-defined material from user access, which is one common choice for browser-based filtering.

4. Client-side Filters

Client-side filters are filtering software that is preinstalled on the device used by an employee or student.

Because such filtering systems must often be installed and set on each individual device, these types of web filters take longer to install than others.

While these sorts of web filters are perfect for small organizations, bigger firms may not want to deal with the effort of installing them on more than a few machines.

Because these sorts of web filters are generally directly put on the device and not controlled by centralized software, anyone with administrative capabilities may easily circumvent them.

5. Network-based Filters

Network-based web filtering is generally deployed at either the transport or application levels of a network.

To protect the network, these sorts of web filters are configured as either a web proxy or a transport proxy. They act as a bridge between outgoing requests and received data.

They also often protect the specific IP addresses of all workstations on the network by only revealing the IP address of the filter to outside users.

6. Search Engine Filters

Filters for search engines filter out inappropriate content from the results a user gets while using a search engine to look up information.

This function is included in the user interface of several search engines. Safe Search options are available on Google and Bing for people who want to filter out inappropriate information in search results.

Both of these search engines have Safe Search enabled by default, however, these filters may be disabled without requiring administrator access.

Search engine filters may also be readily bypassed if the user knows the URL of the site they are attempting to visit or if they use a different search engine that does not have a comparable filter.

Why is Web Filtering Important?

The benefits of web filtering for home usage are rather obvious and will be primarily for the protection of young children. Web content filtering systems, whether hardware or software, are critical for limiting access to undesired web information. Adult sites, malware-infected sites, and sites that may be disruptive to employees or students are examples of undesirable material.

However, while the benefits to the firm may not be as visible, they are far more numerous. Some of the most risks to any organization include hacking, phishing, viruses, and malware. Phishing, for example, is when hackers steal sensitive information via deception, such as tricking employees into logging in to bogus firms in order to obtain login credentials. Without a doubt, the loss or corruption of sensitive data such as login credentials, personal information, accounting information, and legal papers may be disastrous to any business. As a result, content filtering measures are essential. Web filtering provides several advantages for both individual users and businesses.

  • Protection against malware: Malware is, of course, one of the most serious hazards to the organization. Viruses and other types of threats may infiltrate a company's network in a variety of ways, which is one of the key reasons why firms choose to limit internet access. Web filters are capable of detecting malware and blocking access before any download is completed. Exploit kits contain malware that is particularly designed to exploit web browser vulnerabilities via browser extensions and plugins. Unknowingly, a user will visit a malicious URL that contains an exploit kit that, if abused, activates a malware download.
  • Staff productivity has increased: Social networking is a known productivity drain, since it is distracting, consumes large amounts of essential work time, and leads to decreased production. Restricting access has been shown to dramatically enhance productivity. Some sectors, on the other hand, demand social media savvy for day-to-day operations. In these businesses, a separate group of sites, such as online shopping and streaming sites, become productivity drains. There is no excuse for the staff to be watching movies when they should be working. In addition to limiting access to distracting websites, it is critical to evaluate additional channels that may represent a concern, such as downloading dubious files, reading suspicious emails, and responding to unverified contacts.
  • The efficiency of network bandwidth: Non-work-related internet activity consumes a substantial amount of network capacity. By restricting access to certain sites, you boost network bandwidth efficiency and obtain speedier connections. To achieve network bandwidth efficiency, you may educate your staff on the benefits of a continuously fast network or impose limitations on video streaming sites like YouTube.
  • To Assist With IT Policy Implementation: Too many business IT policies are essentially paperwork that lies in a drawer someplace, only to be glanced over by new workers on their first day of work, and then mostly forgotten by everyone else. The second usual situation is that the IT policy is stashed away someplace on the company's intranet, where it goes mainly unread and unheeded by 90% of the workforce. This is a challenging fact for businesses to confront, and teaching people about the perils of phishing and surfing suspicious websites may be difficult. However, by utilizing web filtering, the organization may get more control over how employees use the internet, therefore preventing a lot of malpractice before it occurs.
  • CIPA (The Children's Internet Protection Act ) Compliance: To be in compliance with CIPA, the protections that schools put in place must restrict or filter Internet access to images that are vulgar, include pornography, or are detrimental to kids (for computers that are accessed by minors). CIPA-eligible schools must meet two extra certification requirements:
  1. Minors' online activity must be monitored as part of their Internet safety regulations.
  2. They must include provisions for educating children about proper online conduct, such as engaging with other people on social networking sites and in chat rooms, as well as cyberbullying awareness and reaction.

How Does Web Filtering Work?

Content filtering works by implementing restrictions regarding the sorts of sites that may be viewed using hardware or software-based solutions. Content is classified by categories based on keywords or other similarities across sites (for example, sports, gambling, pornographic, streaming, and so on), and sites in undesirable categories are prevented from accessing the network.

One of the most apparent applications for web content filtering is keeping unwanted information away from youngsters.

Web filters, in general, function in two ways. They can prohibit material based on the site's quality by referencing established lists that describe and categorize popular sites across all content genres. Alternatively, they can analyze the page's content in real-time and block it accordingly.

URL matching: Web requests are compared to the Web Reputation database; the URL, category, user, and highest-priority policy including the requesting user are all resolved, and the necessary action is done.

Real-time rating: Web sites that are not identified in the Web Reputation database are analyzed and a content probability rating is calculated on the fly (in real-time); the page rating and category are then compared to the highest priority policy that includes the requesting user.

A Web page is classified based on the total weighting of all terms on that site, which helps in preventing over-blocking or mistakenly blocking a specific page. Once a URL/domain has been classified and confirmed in another layer of the filter, it is cached locally and maybe regularly uploaded to join the aggregate URL list.

How to Use Web Filtering?

As mentioned at the beginning of the article there are six types of web filtering methods available. Each of them is deployed in different ways and has different requirements, benefits, and drawbacks. You can use one of them which best suits your needs. In the following sections, we will briefly explain to you how you can use browser-based web filtering and network-based web filtering.

How to Use Web Filtering in Chrome?

As a Chrome Enterprise administrator, you may restrict URLs so that users can only browse specific websites. Restricting internet access for individuals can boost productivity while also protecting your company from viruses and dangerous information accessible on some websites.

For simple URL control, use the blocklist and allowlist. Use a content-screening, web-proxy server, or extension if you require more stringent filtering.

Using the URL blocklist and allowlist, you can:

  • Allow access to all URLs except those you block: Use the blocklist to restrict users from visiting specific websites while allowing them to browse the rest of the internet.
  • Block all URLs except those you allow: Use the blocklist to prevent access to all URLs. Then, utilize the allowlist to provide access to a subset of URLs.
  • Create exceptions to very stringent blocklists: Utilize the blocklist to prevent access to all URLs. The allowlist may then be used to provide users access to certain schemes, subdomains of other domains, ports, or specified pathways.
  • Allow the Chrome browser to open applications: Allow particular external protocol handlers so that the Chrome browser may open specific apps automatically.

If you are looking for a solution for a single device you can use browser-based web filtering extensions. Browser-based filters are usually available as browser extensions or add-ons. These filters are simple to set up, but because they are less durable, they are rarely used by enterprises.

Who Uses Web Filtering?

The three most important groups that utilize web filtering are:

Parents who want to keep their children away from information they find objectionable or unsuitable.

  • Businesses: Companies who wish to restrict their employees from viewing websites that are unrelated to their jobs. Furthermore, browser filters can be of great service in preventing malware infection.
  • Schools: Schools utilize web filtering in the same way that companies and parents do, with the hopes of blocking harmful and distracting information while also protecting against malware infection.

Can a Firewall Be Used for Web Filtering?

Firewalls are a type of synchronous web content filtration system.

Firewalls can be physical appliances or virtual appliances that are cloud-based/software-based. Firewalls restrict network traffic to permitted ports, protocols, and IP addresses rather than banning specific websites.

Traditional packet-filtering firewalls filter ports, protocols, and IP addresses at OSI layer 3 (the network layer). While these types of firewalls do block web traffic, they cannot discriminate between specific websites since they cannot recognize URLs or domain names.

Classic firewalls have developed over time into "Next Generation Firewalls" (NGFW), which combine traditional firewall packet filtering with other network filtering capabilities such as web application firewalls (WAFs), web content filters, and intrusion prevention systems. These technologies are often used to protect networks and filter potentially dangerous internet traffic.

Unless you're utilizing a next-generation firewall (NGFW) with an integrated web filter that allows you to block individual URLs, a separate web filter will provide you with significantly more granularity for restricting website access.

What is the Best Web Filtering Firewall?

As mentioned earlier, if you want to choose a firewall solution for web filtering you need to look at the NGFW capabilities of the product. Zenarmor is one of the best web filtering firewall solutions, especially for SMB, school, and home networks. It offers not only free options on open-source firewalls., such as OPNsense, pfSense software, but also enterprise security qualifications.

Zenarmor, as opposed to the typical web filtering solutions, is packed with robust enterprise-grade content filtering technology that enables enterprises to implement comprehensive security capabilities for identifying and blocking malware and advanced threats.

With the help of a huge web category database (more than 300M websites within 120 web categories), it can easily filter any harmful or unwanted websites.

Zenarmor Web Filtering Options

Figure 1. Zenarmor Web Filtering Options

Zenarmor Predefined Web Profiles are divided into four categories:

  • Permissive: This profile has no limitations on online browsing.
  • Moderate: Only dangerous/high-risk site categories are restricted in this profile, such as Illegal Drugs, adults, Pornography, Violence, and Advertisements.
  • High Control: In addition to the categories restricted in the Moderate profile, this profile blocks Forums, Alcohol, Blogs, Gambling, Chats, Dating, Games, Job Search, Online Storage, Social Networks, Software Downloads, Weapons, Military, Swimsuits, Tobacco, and Warez sites.
  • Custom: You may do fully customized web filtering by establishing a new profile.

You may establish user-based policies for content filtering and application control using Zenarmor. As a result, you may not only give free Internet access to your customers but also safeguard them from cyber threats like malware and phishing.

What is the Best Web Content Filtering Software?

Web content filtering solutions are helpful tools for censoring and/or blocking access to restricted web material that is considered harmful or unsuitable. They also offer overall domain name system (DNS) security, preventing users from accessing potentially harmful online pages or IP addresses.

Employees, guests, and customers might have limited access to web material when utilizing the business's wired or wireless network connection. Web content filtering solutions are widely used in businesses today and provide a number of functions that are beneficial to all sorts of enterprises.

Some popular web filtering software can be listed as

  1. Zenarmor: Zenarmor's lightweight and strong appliance-free technology enable businesses to quickly deploy firewalls and security settings as small as home networks or as large as multi-cloud deployments. The packet inspection core is powerful enough to protect against encrypted threats while simultaneously being lightweight and nimble enough to fit in contexts with limited resources. Zenarmor is a software-defined armor system. It's lightweight, nimble, and doesn't require any appliances. This gives you the ability to launch micro firewalls on-demand at the Access, Edge, and Core levels. Micro and mighty packet inspection is so effective that it can even defend against advanced encrypted threats. Implement zero-latency security without having to backhaul data packets between POPs and data centers. The single-pass architecture used by Zenarmor processes packets only once, for all security controls. For an unprecedented level of consistency when enforcing security policies, the same security stack runs everywhere.

  2. Barracuda CloudGen Firewall: Barracuda CloudGen Firewall includes a set of next-generation firewall technologies that provide real-time network protection against a wide range of network threats, vulnerabilities, and exploits, such as SQL injections, cross-site scripting, denial of service attacks, trojans, viruses, worms, spyware, and more. Barracuda firewalls can be set up at many physical locations as well as on Microsoft Azure, Amazon Web Services, and Google Cloud Platform.

  3. Check Point Quantum Security Gateway: Check Point Quantum Network Security protects your network, cloud, data center, IoT, and remote users from Gen V cyber attacks in a scalable manner. Check Point Quantum Next Generation Firewall Protection GatewaysTM safeguard you against the most sophisticated cyber attacks by combining SandBlast threat prevention, hyper-scale networking, a unified administration platform, remote access VPN, and IoT security.

  4. Cisco Umbrella: Cisco Umbrella provides cloud-based security whenever and wherever you need it. It combines several security features into a single product, allowing you to safeguard devices, remote users, and distant sites from any place. Umbrella is the quickest and most effective approach to safeguard your users anywhere in the world.

  5. GoGuardian Admin: With K-12's most comprehensive web filter, you can monitor, manage, and filter any device on your network. A strong AI engine learns and dynamically changes to stay up with changing information. Feel secure knowing that your students will be safe wherever they go. Use educational platforms like YouTube to their full potential, and establish digital norms for students to follow. With GoGuardian's flexible YouTube filtering tools, you can design your school policies to ban comments, keywords, live chat, and entire video categories, as well as complete video categories.

  1. Forcepoint URL Filtering: Forcepoint URL Filtering is the most effective and up-to-date url filtering solution in the business. Forcepoint URL Filtering captures and analyzes up to 5 billion occurrences per day (from over 155 countries), delivering updated threat analytics for Forcepoint solutions at up to 3.2 updates per second, thanks to our ThreatSeeker Intelligence. URL Filtering from Forcepoint reduces malware infections, reduces help desk problems, and frees up important IT resources by blocking web threats. Forcepoint URL Filtering is a transparent, easy-to-deploy filter and security solution that eliminates the need for a proxy gateway. It comes with over 120 security and web filtering categories, hundreds of web application and protocol controls, and more than 60 customizable reports with role-based access.

  2. Securely Filter: On all devices, Securly's cloud-based web filter for schools keeps students safe. From the most sophisticated AI engine in student safety, gain visibility into internet activities, download or email reports, and receive notifications for flagged content.

  3. DNSFilter: DNSFilter makes it simple to build a cost-effective enterprise content filtering system. Without any contracts or commitments, you may be up and operating in minutes. With a cloud-based DNS solution, you can protect your users against phishing, malware, ransomware, and other threats. Prevent your users from accessing improper or unwanted content, such as adult websites or streaming media. DNSFilter is the only DNS threat prevention solution that includes real-time domain analysis, which means we defend you from more attacks.

  1. Symantec WebFilter / Intelligence Services: Symantec Intelligence Services* allows businesses to give risk ratings to millions of websites, allowing them to implement detailed and effective online traffic management even when web filters don't provide a category assignment. Enterprises may tailor and deploy threat risk control policies based on their unique business needs and risk tolerance levels with Symantec. They can block high-risk online traffic while enabling access to sanctioned websites and applications that pose a low risk.
  2. cWatch: Comodo cWatch CSOC enhances your internal IT team's ability to defend your applications by providing advanced security solutions that are simple to adopt, completely managed, and don't require huge upfront costs. Its purpose is to absorb the time-consuming and complex security incident investigation procedure while unloading the high costs of maintaining an in-house security team.