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What is Content Filtering?

The internet has infiltrated almost every facet of our life. It's where we work, study, listen to music, watch videos, look for health-related information, and shop online. The internet is everything to us. It offers many advantages, such as convenience and efficiency, but it also has risks.

It's no secret that the internet has a dark side, the dark web. This includes indecent photos, illegal items, stolen IDs, and much more. The problem is that you don't have to look very far to get inappropriate content. In reality, even the most harmless searches on the internet can turn up unwanted results. This is when the use of content filtering comes into play.

Content filtering is a tool that prevents you from accessing any sites or pages that you consider to be undesirable. These could be sites that are potentially harmful, distracting, or unappealing. You can block specific sites or use keywords to block related content with most content filters. For example, you would like to block pornographic material. To block all search results relating to such terms, you'd use keyword filtering with related words.

The content you filter is determined by the environment in which it is used. In the workplace, content filters are frequently included as software or hardware in the firewall system. If that's the case, the content filter's job is to guard against cyber dangers like phishing and malware. The corporations may be utilizing the filters to keep staff away from things like social media and streaming services.

Content filters are often utilized in schools to protect students and keep them away from potentially distracting websites. Filtering social media, forums, games, or inappropriate sexual content is one example. It also has the potential to safeguard students against cyberbullying, hackers, and scammers. Because of their enormous databases of personal information and the potential for identity theft, cybercriminals frequently target schools. However, if that data falls into the wrong hands, much worse can occur.

How Does Content Filtering Work?

Content filtering works by detecting patterns in content, such as objects inside photos or text strings, that signal undesired content that must be restricted or screened out. Content filters are used in a variety of ways in enterprise networks. Firewalls, mail servers, routers, and domain name system (DNS) servers can all be configured to filter undesired or harmful traffic.

Filtering software can be installed on dedicated servers or hardware appliances can be added to the network. Cloud-based content filtering, like mobile content filtering, is becoming increasingly important. Content filtering should be considered for corporate and employee-owned mobile and other devices, as well as devices used at home, especially by kids.

Character strings are commonly specified in content filters, and if they match, they signify undesired content that should be filtered out. These filters can be set up to filter out certain sorts of content, as well as anything that violates a company's acceptable usage policy. Content-based filtering products frequently involve content-filtering software or hardware. Updated blocklists of possibly harmful IP addresses and domains are also available through subscription services.

Why is Web Content Filtering Important?

In today's increasingly connected, content-driven world, content filtering software solutions are critical to the success of any business. Even the tiniest company requires safe email services at the very least. Surprisingly, 94 percent of malware is sent by email. As a result, no company can afford to overlook content screening software in their infrastructure. Identifying the target use cases is the first step in looking for a content filtering solution.

Content filtering software aids in the blocking of unsuitable, offensive, or security-threatening web content and incoming content such as email. It's a part of a firewall that protects the internet. The software also inspects executable files that are used to install new software on the computer.

The following are some of the most prevalent usage cases:

  • Security: To avoid data leaks and virus downloads as a result of social engineering assaults.
  • Regulatory compliance: To adhere to industry-specific regulations, such as the Children's Internet Protection Act (CIPA), which applies to schools and libraries.
  • Adherence to company policies: To implement company policies such as no gambling or usage of social media on company property.
  • Restricting streaming website: To free up the company network from the undesired payload.
  • Restrictions on violent and adult content: To filter and block offensive and pornographic material.

Organizations are put at risk for objectionable, improper, or illegal content. Consider the following scenario:

  • Allowing pornographic material into the workplace might expose a corporation to sexual harassment lawsuits or create a hostile or humiliating work atmosphere.
  • Spam sites can lead to the installation of malware or other harmful software on work computers.
  • Employee safety might be jeopardized by hate sites or sites with violent content, and the organization as a whole can suffer as a result.
  • Employees can be distracted from ordinary activities by using social media sites, which can decrease productivity.

Content filtering aims to minimize these risks by making improper, unlawful, or offensive content harder to access in the workplace and by exhibiting the company's overall distaste for such content. Content filtering must be implemented across all content channels to be effective. The following are the most prevalent channels:

  • Web: Web site or page screening, as well as bookmarks and other web traffic.
  • Email: Email is screened for spam, viruses, and other unwanted or malicious information. The subject line of emails routed through the filtering mechanism is frequently scanned for this. When a message is received that meets the required parameters, it is sent to the recipient's garbage folder. It may even be returned to the sender as undeliverable in some situations.
  • Executables: The screening of executable files that could unintentionally install dangerous software.

The goal is usually to block access to content that the user or administrator finds undesirable. Some of the restrictions can be implemented at all levels: a national government can try to implement them across the country, an ISP can filter its customers, an employer can filter its employees, and a school can filter its students.

What are the Benefits Of Content Filtering?

Individuals and organizations benefit from content filtering because it protects them from potentially harmful content. Content filtering also performs the following functions:

  • Increases the bandwidth of the network
  • Reduces the risk of malware attacks
  • Increases the productivity of employees
  • Individuals, whether they are children or employees, are protected from viewing anything improper for their age or position.
  • Reduces potential malware visibility by limiting access to malicious websites and electronic mail with malicious content;
  • Reduces the risk of legal liability by preventing the circulation of malicious content;
  • Improves network bandwidth usage by preventing users from accessing unauthorized social media and streaming services, as well as limiting bandwidth-intensive attacks;
  • Protects companies from exploit kits that are camouflaged in other forms of content and sent over email or the internet.

Although content filtering is an important part of enterprise network security, it isn't a complete solution. Content filtering is most efficient when used in conjunction with other security measures like firewalls, multifactor authentication (MFA), and strong authentication protocols like Kerberos. Kerberos is a mechanism for authenticating service requests between trusted hosts across untrusted networks like the internet, and it's built into most major operating systems.

What are Types Of Content Filtering?

Filters can be applied in a variety of methods, including through personal computer software, network infrastructure including proxy servers, DNS servers, and firewalls that give Internet access. Because no single solution can provide total coverage, most businesses use a combination of technologies to provide appropriate content management in accordance with their policies.

1. E-mail Filter

Content filters check each email's contents and utilize that information to determine whether or not it is spam. Because spam email content is generally predictable, such as providing offers, pushing explicit content, or manipulating basic human emotions like want and fear, these filters tend to operate. Spammers that utilize target terms like "special offer" or "discount" multiple times are more likely to activate the filter. Some businesses also employ content filters, which scan emails for offensive language and ban them accordingly.

A procedure of filtering emails that are incoming to the user's mailbox and outbound from the user's server is known as email filtering. Inbound email filtering checks and filters incoming emails for spam, malware, harmful links, and other risks, as well as categorizing and folding them. Outbound filtering examines a user's outgoing emails to ensure that employees follow the company's policies. It also assures that no unapproved spam, malicious content, or sensitive data leaves the server.

Email filtering services come in a variety of shapes and sizes, with enterprises able to pick between cloud-based and on-premise deployment options based on their needs.

2. Search Engine Filter

Some search engines provide a feature called search filtering that helps users restrict the number of improper search results displayed to them. Many search engines, including Google and Bing, allow users to activate a safety filter. When this safety filter is turned on, it filters out all of the search results that contain inappropriate links.

Generally, thumbnail images connected with sites that meet the search criteria appear in Internet search engine results. Your program prohibits users from accessing the full site if those thumbnails are associated with restricted sites, but it does not prevent the search engine from presenting the image. When you activate search filtering, the search engine function prevents thumbnail images from restricted sites from appearing in search results.

SafeSearch is a search engine function that acts as an automated filter for highly offensive and pornographic materials or inappropriate content. SafeSearch isn't completely perfect, but it's designed to help you block explicit results from your search engine results, such as porn. SafeSearch is currently supported by Google, Yandex, DuckDuckGo, Bing, and Pixabay.

When a user uses a search engine, the results are filtered; however, if a person knows the full URL of a website, they can visit it without using a search engine or filtering it. Thus, URL filtering can be used, too. URL Filtering provides visibility and control over the network's online traffic. The firewall can separate web traffic into one or more URL categories when URL filtering is enabled. Policies can then be created that describe allowing, blocking, or logging (alert) traffic based on the category it belongs to.

3. DNS-based Content Filtering

The Domain Name System (DNS)'s function is basic. It connects a domain name to an IP address. DNS-based web filtering protects the DNS against attacks and ensures a secure surfing environment. Users' efforts to view malicious sites, such as those used for virus distribution or phishing, are blocked using DNS-based filtering. Instead of utilizing an organization's DNS infrastructure, which is subject to attack, a third-party service provider is used to discover websites. The DNS query is done through the service provider, who keeps a database of classified domains and webpages.

The DNS lookup is executed through the service provider, who keeps a database of classified domains and webpages. The speed of lookups remains unaffected, therefore end-users will not notice any difference. The distinction is that kids will only be able to browse safe websites in most cases. They will be linked to the right IP address if they attempt to access a website that is not dangerous. If the website they're trying to access is found to be malicious or highly dubious, they'll be redirected to a local IP address that contains a DNS block page informing them that they can't connect.

4. Internet Filters

When software is used to block computer users from accessing particular sites or areas of the internet, this is known as internet filtering. Anyone who runs or maintains a network, including businesses, schools, organizations, and public access points like libraries, can install Internet filters.

An Internet filter is a software that limits or regulates the content that an Internet user may access, particularly when used to limit material provided over the Internet via the Web, email, or other methods. Content-control software decides whether or not certain types of content are available.

Such restrictions can be imposed at various levels: a government can attempt to impose them across the board (see Internet censorship), or they can be imposed on an ISP's customers, an employer's employees, a school's students, a library's visitors, a parent's child's computer, or an individual user's computer.

The goal is usually to restrict access to content that the computer's owner(s) or other authorities may find objectionable. Content restriction can be classified as internet censorship when it is enforced without the user's consent. Some content-control software includes time-control features that allow parents to limit how much time their children can spend on the Internet, playing games, or doing other computer-related activities.

To keep your children safe and secure online, you need to invest in the best internet filter software available. If you use a high-quality filter, you may let your children surf the web knowing that they will be considerably less likely to come across improper content. The top internet filter devices come with a variety of features that will keep your children safe online. You can block harmful websites, limit your children's access to social media, and even prevent them from downloading files. It protects them while also protecting your electronics. It's critical to be sure that any software your children use will operate on their devices, whether they're the best smartphones, laptops, or home PCs. Some filters operate on all operating systems, while others only work on a few.

5. Proxy Content Filtering

Proxy and content filtering utilize programs or even firewalls to screen network traffic to prevent access to unwanted, dubious, or explicit information. This might include harmful or inappropriate information on websites or in emails.

A content-filtering web proxy server allows administrators to manage the material that is delivered over the proxy in one or both ways. It's widely used in both commercial and non-commercial organizations (particularly schools) to guarantee that Internet usage follows a set of guidelines.

User authentication is frequently supported by content filtering proxy servers to manage online access. It also generates logs, which are used to provide detailed information about URLs visited by individual users or to track bandwidth use data. It may also connect with daemon-based and/or ICAP-based antivirus software to enable real-time screening of incoming material before it enters the network, which protects against viruses and other malware.

Many organizations, schools, and institutions limit the websites and internet services that may be accessed and used within their facilities. Unwanted information is also censored by governments. This can be accomplished via a content filter (both commercial and free tools are available) or a cache-extension protocol like ICAP, which permits plug-in expansions to an open caching architecture. Several approaches, such as URL or DNS blacklists, URL regex filtering, MIME filtering, or content keyword filtering, can be used to filter requests. The material is subsequently retrieved by the proxy if the requested URL is acceptable. On the return path, a dynamic filter can be applied at this point. JPEG files, for example, maybe restricted based on flesh tone matching, or language filters could identify undesirable words in real-time. If the material is refused, the requester may receive an HTTP fetch error.

The majority of online filtering firms employ an internet-wide crawling robot that determines the likelihood of material being of a specific type. Manual labor is then used to fix the database as a consequence of complaints or recognized faults in the content-matching algorithms. Some proxies analyze outgoing material for data loss prevention or dangerous software detection.

6. Web Filter

A Web filter, often known as "content control software," is a piece of software that limits the websites that a user may access on his or her computer. These filters can function with an allowlist or a denylist: The former only allows access to sites that the person who set up the filter specifically specified, whereas the latter limits access to sites that the filter's criteria find undesirable. These applications look at the desired site's URL and examine the content for banned terms before deciding whether to block or allow the connection. In many aspects, this form of filtering is comparable to block and allow list filtering, although it has a little greater reach. Websites that include particular keywords or predetermined material will be filtered out by keyword and content filters (such as pornography, for example).

Filters are frequently installed as a browser extension, a stand-alone software on the computer, or as part of a larger security program. They can also be placed on the network side, by either an ISP or a company, to limit numerous users' access to the Internet at the same time. Some search engines additionally provide basic filters that may be used to filter out sites that aren't relevant to the search.

Three major groups use web filtering:

  • Parents who want to keep their children away from information they find objectionable or improper.
  • Businesses want to restrict their employees from visiting websites unrelated to their jobs. Browser filters can also help prevent malware infection in some cases. Schools utilize web filtering in the same way that companies and parents do, with the hopes of blocking harmful and distracting information while also preventing malware infection.

Web filtering may be a useful tool to assist avoid cyberattacks or loss of security for anyone worried about accessing the internet safely. Monitoring and filtering what workers share allow IT regulations to be actively enforced while also preventing data loss. Because a firm's security is vital, any leak of confidential information would be detrimental. A recent law, the CIPA (Child Internet Protection Act), has made it necessary for organizations that provide public internet access, such as schools or libraries, to deploy a filtering system or risk losing funds. Web filters can prevent users from visiting websites that execute dangerous malware on their computers.

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, and pfSense software but also enterprise security qualifications.

Zenarmor is a strong policy and reporting engine that combines malware, and virus protection with a complete web security and management solution. Advanced capabilities allow businesses to react to new needs such as social-network regulation, remote filtering, and visibility into SSL-encrypted communications. Zenarmor processes the request and makes real-time queries to SVN Cloud and decides whether to block or allow it. Checked over 300 million websites in more than 120 categories within milliseconds.

There are four types of predefined Web Profiles:

  • Permissive: This profile allows unlimited web browsing
  • Moderate Control: Adult, Pornography, Illegal Drugs, Violence, and Adverts are blocked in this profile's Moderate Control setting.
  • High Control: After the moderate profile, this profile blocks the following categories: Alcohol, Blogs, Chats, Dating, Forums, Gambling, Games, Job Search, Online Storage, Social Networks, Swimsuits, Tobacco, Warez Sites, Weapons, and Military
  • Custom: You can customize your profile as you want.

Zenarmor: Web Controls

Figure 1. Zenarmor: Web Controls

What are Content Filtering Best Practices?

Best practices of content filtering are listed below:

  • Allowing for remote deployment: As individuals work from more remote places, content filters must be able to be deployed remotely. Client-side instruction for workers to install filters themselves, a distant installation by IT, or platforms with built-in filters are all options for distribution.
  • Covering the whole threat spectrum using content filtering: Make sure that content filtering covers the entire threat spectrum. Data loss prevention (DLP) and dynamic adult image analysis are used to defend against credential theft, mobile malware, and virus outbreaks.
  • Using category-based filters: Organizations can use category-based filters to limit access to certain types of websites, such as adult. gaming, online shopping, and social networking sites. This allows for more adaptable policy implementation and better control over how users use the internet.
  • Blocking certain URLs: Organizations can use content filters to exclude specific URLs from rules that have been imposed. As a result, rather than banning whole websites, they allow specific pages to be blocked.
  • Implementing URL filtration: URL filtering allows businesses to avoid online-based dangers and monitor employee web activity without limiting user access.
  • Implementing schedule-based access: Employees who work remotely on their devices sometimes require diversions after lengthy periods of labor. Organizations can use a schedule-oriented content filtering technique to set quotas of non-work-related online access or access to sites at specified times of the day.
  • Utilizing automatic reporting: Businesses need to know how effective their content filters are and what kinds of content their employees are accessing. Automatic reporting is becoming more common in content filters, providing real-time data and insight into employee activities.

Does Firewall Do Content Filtering?

Content filtering programs are commonly used by organizations to control content access through their firewalls. They can also be used by home computer users. Content filtering is often built into internet firewalls to block access to information. When it comes to social networking sites, companies use content filtering tools to improve security and enforce corporate policies. Most firewall software also filters web content to help prevent viruses, phishing attacks, malware, and ransomware.

How to Use Content Filtering?

Users may use a single technique or may merge two or more of the mechanisms for content filtering. Content may already be blocked by existing network security technologies, such as firewalls. Other software solutions, as well as dedicated appliances and cloud-based content filtering systems for distinct departments, locations, and business units, can improve that function. Firewalls are regarded as a bare minimum in terms of network security to protect businesses against attacks. It would be helpful to learn how inbound and outbound firewall rules, unwanted content, and intruders can stay out of the network.

Zenarmor provides an efficient and powerful Web content filtering solution, It has rich database which includes more than 300 million websites with 120+ categories. It's user-centric design puts you in command. If the category does not exist in the list, you can create one by entering a name in the New Category field and clicking the plus sign. Zenarmor allows you to block individual categories by clicking on the green check icons located on the left side of each web category. Web categories can be created and managed with a single click. You can either enter each website individually or import them in bulk from a file to create a custom web category.

How to Enable Content Filtering?

The following are some options for enabling content filtering:

  • Configuring existing systems to filter out prohibited content, such as firewalls, email servers, routers, and DNS servers.
  • On current or dedicated business servers, installing specialized content filtering software.
  • Integrating content filtering hardware appliances into the company network infrastructure.
  • Using cloud-based content filtering solutions to filter material without the need for additional gear or software.

In Zenarmor you can easily enable Content Filtering through the web control page.

How to Change Content Filtering Settings?

With over 4.5 billion websites on the internet, it is very difficult for content filters to remove all harmful information. A content filtering router isn't always perfect, and it can cause mistakes. It is usually better to seek a comprehensive content filter that allows for regular upgrades and modifications as required. Zenarmor is one of the most effective filtering programs on the market. It was created with schools' and enterprises' needs in mind. In Zenarmor, same as enabling the content filtering process, you can change the content filtering setting through the web controls page.

How to Turn off Content Filter?

Users can deactivate content filtering on their router or through their search engine to remove it.

Zenarmor users can turn off the content filtering setting by disabling web control rules.

How To Remove Content Filtering?

Users can keep secure on the internet by using content filtering. It can, however, restrict access to legal websites or those that are necessary for work. Certain content filtering firewall rules, for example, may ban the website breastcancer.org. Internet users can avoid this by deactivating content filtering on their network or through their search engine.

The following are the steps to take:

Disabling Content Filters on Routers:

By removing a router-based content filter, you can get access to specified websites:

  1. Open the primary settings file after logging into the router's network setup software.
  2. Select the "Blocked Sites" option from the drop-down menu.
  3. Select "Delete" or "Disable" from the drop-down menu for the filter that needs to be deleted.
  4. Select "Apply" from the drop-down menu. The content filter should be turned off now.
  5. Log out of the network configuration settings on the router.

Disabling Search Engine Filters:

Google Safe Search may also be used to apply content filters, which can only be changed by administrators. After you've changed the filter setting, you'll need to provide a password to access it. Furthermore, search settings tend to block large sections of content without notification.

To turn off these filters, do the following:

  1. To get the relevant site URL, go to the Google search settings page and look under "Resources."
  2. Scroll down to the "Safe Search filters" option and turn off the filter so that "No filtering" appears.
  3. The update should now be active if you click the "Save" button.