Typically, best firewall settings include action components that decide if a firewall will permit or block traffic based on a match feature. For instance, if the traffic meets the rules specifications, then it connects to the network. That way, organizations can leverage the firewall to block presumably malicious traffic in public networks from getting to internal networks.

It is vital to consider potential security threats when modifying firewall rules to prevent unforeseen issues. We have put together a list of the best practices for fine-tuning your firewall settings to help you maximize the security tool’s effectiveness. It is necessary to understand that the exact procedures for modifying your firewall settings differ based on the firewall make and model, as well as whether it is a software or hardware-based firewall tool. However, regardless of the firewall technology in use, following these best practices will help you get the best out of your solution.

1.     Document the Firewall Rules

Unquestionably, an organization has thousands of firewall rules and policies crucial to its performance. Furthermore, not all rules are mutually exclusive, and some directly affect another set of rules. The simplest mistake can, in this case, trigger a massive security loophole that allows malicious traffic to sneak in while blocking legitimate traffic. In effect, it is vital to document all firewall rules for enhanced security and optimum performance.

Organizations need to document every firewall rule to establish the rule’s actions. Documenting existing and any new rule involves tracking information such as the rule’s purpose, the affected application and web server, the affected users and devices, the date the rule was created and the expiration date, if applicable, and the rule’s author.

2.     Establish a Proper Firewall Rule Change Procedure

After documenting your firewall rules, it is crucial to create a formal change procedure. By and large, you will need to update your specific rules and overall firewall policy for any new services, servers, devices, or users added. Before making any changes, an organization should establish a formal change procedure that outlines the change request process for users or devices requiring modifications to specific configuration changes. PSI DSS Guide recommends that security administrators plan the process of adding, changing, or deleting firewall rules so that the performance of the existing ruleset is not adversely affected.

Additionally, the procedure should feature a formal review process for analyzing new modification requests and establishing the best course of action for security rules and practices. You can also add a way of testing the new change requests on the production firewall rules and default settings. On top of that, the security rules change document should provide detailed information on ways to deploy the tested now modifications into production and a process to validate that the new settings are operating fittingly. Finally, there needs to be a method to ensure you track and document all changes.

3.     Ensure Your Firewall is Secure

Securing your firewall is a significant first line of defense in configuring and managing a secure firewall. Always ensure that your firewall is not performing unsafe actions properly. PSI DSS Guide lists the basis firewall security steps as follows:

• Disable the simple network management protocol (SNMP)
• Rename, disable or delete any default user account
• Change all default passwords
• Create additional administrator accounts based on responsibilities for multiple personnel who will manage the firewall

4.     Default Block Behavior

Security experts recommend that you start by blocking all traffic and unauthorized access by default and only allow specific traffic to identified applications and servers. This default configuration sets a baseline control over the traffic and downplays the likelihood of a cyberattack. Markedly, you can achieve the default block rules behavior in firewalls by configuring the last rule in access control lists to block traffic. You can then add explicit firewall rules to modify the configurations based on the platform.

5.     Set Explicit Firewall Rules after Default Block Behavior

Set the most explicit firewall rules at the top of the rule base. The rules act as a starting point for matching traffic by managing what the firewall permits or blocks. A rule base classically works on a top-down protocol, with the first rule in the list performing the initial action. In this case, if the first rule permits the traffic, the remaining rules will not assess it again.

In most cases, standard regulation authorities such as PCI DSS, NIST, ISO, SANS, and NERC guide security administrators to evaluate network security from a firewall configuration perspective. As an example, SANS Institute’s Security Consensus Operational Readiness Evaluation Firewall Checklist provides the following order that you can adopt during the firewall setup:

• Anti-spoofing filters – blocked private addresses and internal addresses appearing from the outside
• User permit rules – for example, allow HTTP to public webserver
• Management permit rules – for instance, SNMP traps to the network management server
• Noise drops – as an example, discard OSPF and HSRP chatter
• Deny and alert – alert systems administrator about suspicious traffic
• Deny and log – log remaining traffic for analysis

Since firewalls operate on a first-match basis, it is essential to follow a structure such as the one recommended by SANS to ensure that suspicious traffic is blocked instead of inadvertently allowing them in by failing to follow the correct rule order. 

6.     Set Cleanup Rule/ Explicit Drop Rules

Properly configured firewalls designedly drop all blocked traffic. You can place a cleanup rule at the bottom of each security zone context as a safeguard to stop unauthorized traffic from passing through the firewall. You can define the cleanup rule (any-any-any drop rule) that provides a catch-all mechanism as follows:

              Source = ANY

              Destination = ANY

              Service/Application = ANY

              Action = DROP

              Logging = Enabled

7.     Modify Accept All Rules

The “Accept All” rule can cause traffic to block a process or system from reaching its full productive potential. Therefore, it is essential to remove it from your firewall policy and only allow legitimate IP addresses to private networks connections.

8.     Audit Logs

Customarily, security tools like Windows firewall come with built-in reporting tools that provide detailed information about your network traffic. So naturally, the tool generates firewall logs for auditing any changes or anomalies that might require modifications to firewall settings. Better yet, maintaining audit logs can also help in firewall optimization.

PSI DSS Guide states that firewall audit tools automate analyzing complex and bloated rule sets to validate and demonstrate enterprise access controls and configuration change management processes. eSecurity Planet also notes that some of the most advanced tools include artificial intelligence or machine learning capabilities that can help you spot essential details that you might have otherwise missed. In this case, logs provide data that show unused or activated firewall rules. Log data also reveals false positives on traffic that was not supposed to trigger an alert. Overall, audit logs present vital information that guides changing firewall rules to improve service and enhance security.

9.     Maintaining Firewall Rules

Networks constantly change by gaining new services, devices, and users. Consequently, organizations need to add or review firewall rules to allow access to new services and applications. Sometimes the process involves deleting old firewall rules. All things considered, it is a best practice to establish a regular maintenance schedule to make updated changes to the firewall policy.

PCI DSS requests actions like deleting any unhelpful and unused firewall rules and expired ones to clean up your firewall policy. Additionally, the regulation recommends disabling unused connections and source/destination/service paths in firewall rules. Security administrators should also apply object naming conventions that make the rule base easier to understand.  

10. Patching / Updating the Firewall

Always keep the firewall updated with the latest patches and firmware. Failure to update the security tool leaves it vulnerable to attacks and renders firewall rules useless. Next-generation firewall vendors regularly release software updates to address new potential security threats by making minor changes to the solution. Subsequently, it is essential to keep updating your firewall software to ensure your IT environment is secure with no potential security gaps.

11. Automating the Firewall

Organizations embrace new technologies that require constant updates to firewall rules. Apart from that, network administrators manage several applications, servers, devices, and users, requiring different new rules and modifications of existing ones. As a result, IT personnel may get flooded with many requests requiring time and resources to analyze and determine the best course of action. Such constraints can lead to outdated, unused, unaudited, and overly permissive firewall rules, which downgrades firewall performance and can result in increased cyberattacks.

Fortunately, an automation solution for firewall configuration updates can help follow the established firewall rule change procedures. In addition, eSecurity Planet reveals that automation typically enables you to prevent mistakes and avoid firewall failures. Better yet, the solution allows administrators to perform higher-level functions necessary for increased security. 

Conclusion

Ultimately, these best practices for firewall configuration guide you in setting a security mindset and maintaining a secured network and system. In any business, firewall configuration changes are vital to network security, and it is indispensable to streamline rule changes and remove configuration gaps. Besides that, it is crucial to record all configuration changes in real-time and generate logs or trigger notifications whenever a security administrator modifies a rule.

In effect, security personnel must strike a balance between the need for enhanced security and the need for fast performance when configuring network firewalls. This article articulates steps they can take to fine-tune their firewall rules to achieve an ideal balance between security and speed.

Using the best firewall for Android devices is essential in today’s threat environment. Android operating system commands the lion’s share of mobile users globally as of September 2021, accounting for 72.44% of the mobile operating systems market globally. The closest competitor, iOS, has a market share of only 26.75%. Additionally, 80% of the more than 313 million smartphones and tablets shipped between April and July 2021 were running the Android OS.

Undoubtedly, Android is the most popular OS on the planet. The popularity hinges on the OS’s open-source nature, which permits popular mobile phone manufacturers, including Huawei, Samsung, and Xiaomi, to run their devices.

However, the popularity of Android devices exposes users to numerous online risks. For example, Check Point researchers recently discovered cloud misconfigurations that allow misuse of storage, notification managers, and databases. The misconfigurations exposed the data of more than 100 million users, including passwords, names, and email addresses, while causing corporate resources to be vulnerable to attacks. More concerning, recent research found that at least 60% of Android apps are vulnerable to multiple attacks, with the average number of security flaws totaling to 39 per app.

Why Do You Need the Best Firewall for Android Devices?

The security approaches of computers and Android devices are different, and most people don’t regard a firewall application as critical in securing a mobile device. On the contrary, installing a firewall on an android smartphone provides users with full control over apps with internet access to protect mobile data from attacks. Besides, a firewall application permits users to determine android apps that can access and use an android phone network, enabling monitoring of app data usage.

In addition, using the best firewall apps allows you to restrict background data when connected to an internet connection, which extends a device’s battery life. Also, for android games that require an internet connection, you can use a firewall to block annoying ads by preventing the apps from accessing the internet. Ads can be annoying since they pop up every other time.

More importantly, any android device is susceptible to breaches and attacks. As a result, it is pertinent to take recommended precautions to secure personal information stored in android mobile devices by using one of the best firewall for Android Devices options. Enabling the advanced features that come with android firewalls is the right step towards protecting against potential cyber-attacks and breaches. Enabling a firewall app allows users to control the data that specific apps can share or apps that can access the internet.

Lastly, similar to firewalls installed in a network or computer, an android firewall acts as a gatekeeper. Hence, an android firewall can filter network traffic to block malicious traffic from entering your device. That implies that a firewall can help filter incoming traffic and outgoing traffic to prevent harmful network interactions.  

Enable a Firewall in Three Easy Steps

An android firewall allows users to control app interactions with external networks to safeguard data and applications. Fortunately, there are numerous firewall applications to choose from, with each app boasting additional features designed to offer you complete privacy. You can enable a firewall in three easy steps, which are:

1. Identify the most suitable firewall app: Different firewall applications provide different functionalities and features. Therefore, the first step should be identifying a suitable firewall app that addresses your security issues. A search of firewall apps on the Google Play Store can provide some excellent choices.  
2. Does your phone require root access? Mobile phones running earlier versions of Android need root permissions to install some firewall apps. In addition, rooted android devices provide super-user privileges where users can write or read system files or modify system configurations.
3. Install the firewall app of choice: Once you identify a suitable app, install it and accept the necessary permissions, create a VPN connection if required, and configure the firewall to ensure optimized protection.

Best Firewall for Android Devices

1.      AFWall+

AFWall+ is one of the android firewalls that require root access. It is a root firewall app that enables users to control their device’s internet activities better. For example, you can use AFWall+ to control internet access for each app despite whether it is an installed or system app. Notable best features of AFWall+ firewall include the ability to:

• Export profile settings, preferences, and firewall rules
• Hide applications
• Lock and password-protect AFWall+ configurations
• Support profiles for multiple users
• Support tether, VPN, and LAN

2.      NoRoot Data Firewall

NoRoot Data Firewall has a clean and simple interface. The firewall’s default configurations notify users once a particular app tries to connect to the internet. Hence, you may decide whether to permit or deny an app from accessing internet traffic. In addition, NoRoot Data Firewall offers access control capabilities where users can control access of individual apps, default mobile data or internet usage, and app behavior when connected to wireless networks.

Moreover, NoRoot Data Firewall logs the network activity of each app and allows users to analyze the IP addresses or websites a specific app connects. Additional features include the ability to block access to IP addresses or individual domains, prevent images from loading to maximize data usage, capture packets, modify DNS server, and throttle bandwidth.

3.      VPN Safe Firewall

As the term implies, VPN Safe Firewall is one of the best firewall for android options that protect a user’s online activities. It has an inbuilt virtual private network that encrypts traffic to prevent access from prying eyes. Also, VPN Safe Firewall comes with added functionalities designed to minimize data usage and preserve battery life. VPN Safe Firewall has a simple user interface that enables configurations per-app basis. Moreover, VPN Safe Firewall notifies users by default once an app attempts to establish an internet connection. VPN Safe Firewall is a free app designed to work with different networks, including LTE, WiFi, 3G, and 4G networks.

4.      NetPatch Android Firewall

NetPatch Android Firewall does not require root access to protect your device. Similar to most android firewall apps, NetPatch Android Firewall permits users to block or allow any IP address, Hostname, or network-based app. In addition, NetPatch Android Firewall stands out from most firewall apps since it enables users to customize each app how it can interact with the internet, even when a device’s screen is turned off.

NetPatch Android Firewall also supports ShadowsocksR and Shadowsocks proxies, a capability not present in most android firewalls. You can use NetPatch Android Firewall as a free app or access premium functions by making in-app purchases. Some advanced premium version features include supporting CIDR network addresses, creating IP or domain groups, blocking apps from accessing specific domain names, and viewing network logs.

5.      Mobiwol NoRoot Firewall

Mobiwol firewall app permits users to prevent individual android applications from accessing the internet via mobile data connection or WiFi networks. Lack of complicated settings and ease of use are some of the factors that make Mobiwol appeal to most android users. Essentially, you can configure the system apps or installed apps that can access the internet by just selecting them.

Mobiwol firewall further notifies users of each app’s data usage to inform whether to restrict some apps from using more data. If the apps use data to the set limit, Mobiwol prevents further internet access or the use of mobile data. The app provides valuable features without the need to configure confusing or advanced options.

6.      InternetGuard Data Server Firewall

InternetGuard Data Saver Firewall is one of the most helpful android firewalls used to block outgoing and incoming internet traffic. While it is a relatively new app on Google Play Store, InternetGuard Data Saver Firewall protects user devices efficiently since it can block all network traffic with a single tap.

Moreover, InternetGuard Data Saver Firewall is easy to use as it lacks complicated configurations or settings present in most firewall apps. InternetGuard Data Saver Firewall also provides numerous advanced features designed to enhance android device security posture. For example, you can protect your privacy by using the no tracking of user data. It also supports various network protocols, among them being UDP, TCP, IPv6, and IPv4 protocols.

7.      NoRoot Firewall

NoRoot Firewall is one of the best Android firewall apps for unrooted mobile devices. It is a feature-rich firewall app that provides users with complete control of device applications. Specifically, NoRoot Firewall enables users to determine the applications that access an internet connection or restrict the access.

Besides, you can gain more nuanced control using NoRoot Firewall by selecting individual apps permitted or prohibited from accessing the internet using mobile or WiFi data. Additional features include blocking access to specific IP addresses and websites. On the downside, NoRoot Firewall does not support IPv6 network protocols and may, therefore, not work on devices using the LTE network connection.

8.      LostNet NoRoot Firewall

LostNet NoRoot Firewall provides numerous which you can configure over a simple and easy-to-use interface. The firewall app enables Android users to not only prevent apps from connecting to the internet but also restrict apps from accessing specific regions or countries. Similar to most non-root firewalls, LostNet NoRoot Firewall manages network traffic through a local VPN. Therefore, LostNet NoRoot Firewall can protect an android device from harmful websites and domains by blocking ad popups.

One of the reasons most users consider the LostNet NoRoot Firewall as a perfect solution is that you can prevent apps from connecting to the internet at specific times. Additional useful LostNet NoRoot Firewall features include network traffic monitoring, the ability to capture data packets for analysis, support profiles of different users, instant notifications and alerts, and the power to prevent apps from accessing untrusted networks. However, LostNet NoRoot Firewall is not a free app, and users must part with approximately $0.80 to access the premium version.