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Best Firewall Management Software Tools

Organizations must ensure that the appropriate security policies are in place in order to preserve their investments and maximize security efficacy. However, as networks expand and flourish, network security professionals must manage a greater number of siloed security devices from more vendors than ever before. IT teams cannot make full use of their existing firewall investments and adopt firewall rule best practices without centralized management of their network security policies. Because firewall security teams are unable to connect and see clearly, they are vulnerable to compliance concerns, firewall audit failure, and cyber-attacks.

Firewall Security Management Software allows for the monitoring and configuration of firewalls from a single interface. The software can monitor real and virtual firewalls, as well as routers, load balancers, and switches. The software can correlate network behavior to potential attacks using real-time event tracking. If firewall security management software identifies changes to security policy or potential vulnerabilities caused by policy modification, it can send notifications. Best practice information is leveraged by firewall security management software to mitigate these security issues.

Any standalone or commercial firewall includes management capabilities. The breadth and depth of the software's administration capabilities are what distinguishes firewall security management as a distinct category.

1. Skybox

Skybox® Firewall Assurance simplifies firewall management tasks across a wide range of firewall vendors and complex rulesets. It simplifies compliance management by ensuring that your network's status is always in accordance with the security policy design. Furthermore, Firewall Assurance aids in the application of DISA STIGs and CIS benchmarks.

Skybox also aids in the reduction of risk on firewalls, allowing them to better secure your assets. Firewall Assurance can detect vulnerabilities on firewall devices using configuration data, OS versions, and advanced analytics.

Skybox Firewall Assurance

Figure 1. Skybox Firewall Assurance

Skybox Firewall Assurance allows you to centrally manage classic, next-generation, virtual, and cloud-based firewalls, as well as secure access service edge (SASE) solutions from many manufacturers.

  • Easily and effectively manage east-west and north-south traffic.
  • Improve and automate cyber hygiene chores like logging and firewall security settings.
  • Find and remove firewall rules that are redundant, shadowed, or excessively permissive.
  • Automate the process of managing firewall changes.
  • [Best practices for firewall security policies]((/docs/network-security-tutorials/best-practices-for-firewal-rules-configuration) should be implemented.

Skybox supports major FW vendors like Check Point, Cisco, Fortinet, Paloalto, VMWare.

2. Firewall Builder

Firewall Builder, abbreviated fwbuilder, is a universal GUI-based firewall configuration and management tool that supports the extended access lists of iptables (Netfilter), ipfilter, pf, ipfw, Cisco PIX, and CISCO routers, allowing network and sysadmins managing larger networks or hobbyists managing home-based networks to simplify management tasks. Firewall Builder is compatible with a wide range of common operating systems, including Red Hat, Mandrake, SUSE, FreeBSD, MacOS X, and Windows.

Firewall Builder

Figure 2. Firewall Builder

Firewall Builder was created to make firewall management easier and more efficient. Instead of entering instructions, features like shared objects, drag-and-drop GUI, and search and replace are meant to allow users to focus on choosing what traffic their firewall policies should allow or refuse.

Firewall command line syntax can be complicated and difficult to memorize. Add to that the reality that tiny syntactic changes can occur between versions of the same device, and even basic adjustments might take a long time. Instead of always searching for the proper command, Firewall Builder allows users to easily design even the most complicated firewall rules using user-defined GUI components.

Making adjustments is simple since Firewall Builder is built on user-defined components that can be reused in numerous firewall policies. Do you need to change the IP address of a server? Simply change the object and recompile the policies for firewalls that utilize it.

The integrated rules analysis and syntax checking in Firewall Builder help you prevent costly mistakes. Every time, the compiler creates rules with the correct command syntax. There are also built-in protections to assist you to prevent typical errors like changing a firewall rule or locking yourself out of a device.

The following are the characteristics of Firewall Builder:

  • Over 100 preconfigured objects for the most common and extensively used protocols and services, as well as the ability to construct custom objects specifying IP, ICMP, TCP, UDP, or custom services. Firewall Builder may also generate objects that define hosts, networks, and address ranges.
  • Powerful wizards and other tools to help you kickstart your firewall policy and get it right the first time. Wizards provide standard principles for common network configurations, which may later be expanded and altered by hand.
  • The network discovery application automates the development of many objects.
  • A policy management method that is object-oriented: Any modification to an object is instantaneously reflected in all policy rules of all firewalls that use that object. The object database for many firewall configurations is shared.
  • Creates scripts for setting interfaces, IP addresses, SNMP, NTP, and logging parameters, as well as other features of the firewall system.
  • Convenient GUI that enables conventional copy/paste operations for both text strings and network objects, as well as drag-and-drop policy modification.
  • Using RCS to configure version control.
  • Designed for managing dedicated remote firewalls as well as local firewall settings on servers, workstations, and laptops.
  • Supports a variety of firewall systems, including Cisco PIX and open source firewalls such as iptables, ipfilter, and pf. It may print a single object, a firewall policy, the entire hierarchy, or export it to a text file in plain text or HTML format.

3. AWS Firewall Manager

AWS Firewall Manager streamlines administration and maintenance chores for a number of safeguards, including AWS WAF, AWS Shield Advanced, Amazon VPC security groups, AWS Network Firewall, and Amazon Route 53 Resolver DNS Firewall, across numerous accounts and resources. With Firewall Manager, you only need to configure your safeguards once, and the service will apply them to all of your accounts and resources, even as you add new accounts and resources.

Firewall Manager offers the following advantages:

  • It aids in the protection of resources across accounts.
  • Assists with the protection of all resources of a specific sort, such as all Amazon CloudFront distributions.
  • Assists in the protection of all resources with defined tags.
  • Automatically adds protection to resources uploaded to your account.
  • Firewall Manager offers the following advantages:
  • It aids in the protection of resources across accounts.
  • Assists with the protection of all resources of a specific sort, such as all Amazon CloudFront distributions.
  • Assists in the protection of all resources with defined tags.
  • Automatically adds protection to resources uploaded to your account.

Firewall Manager is especially beneficial when you want to protect your entire organization rather than just a few individual accounts and services, or if you often add new resources that need to be protected. Firewall Manager also allows you to centrally monitor DDoS attacks throughout your entire enterprise.

4. Cisco Firepower Management Center

The Cisco® Secure Firewall Management Center (Formerly Cisco Firepower Management Center) serves as your administrative hub for administering important Cisco network security products. It offers centralized management of firewalls, application control, intrusion prevention, URL filtering, and enhanced malware protection. Manage a firewall, control applications, and investigate and remediate malware outbreaks quickly and easily. It is an important component of the comprehensive and integrated Cisco Secure portfolio, providing in-depth analysis, streamlined security management across the network and cloud, and expedited incident investigation and response across your Cisco and third-party technologies.

  • Exceptional visibility into what is happening in your network and cloud, allowing you to identify what needs to be safeguarded.
  • Detects suspicious/malicious traffic fast and generates specific rules to stop the attack from progressing.
  • With a graphical representation of all the devices infected by the attack, built-in forensics provides a complete study of malware to safely remediate.
  • Creates firewall rules and manages thousands of commercial and bespoke applications in your environment.
  • Shares context with Cisco Secure Workload, allowing network firewalls to be "workload aware" for greater protection of dynamic applications throughout your environment.
  • Specifies the levels of intrusion protection, URL reputation rules, and malware threat defense policies. It addresses issues such as: "When network traffic from a specified country arrives using this specific application with a file attached, I may use this degree of intrusion inspection to examine the file for malware and send it to the integrated sandbox."

The Firewall Management Center serves as the centralized event and policy manager for the following systems:

  • Cisco Secure Firewall Threat Defense (FTD), both on-premises and virtual

  • Cisco Secure IPS (formerly Firepower NGIPS)

  • Cisco Firepower® Threat Defense for ISR

  • Cisco Malware Defense (formerly Advanced Malware Protection, or AMP)

Cisco Firewall Management Center

Figure 3. Cisco Firewall Management Center

The Firewall Management Center (FMC) gathers real-time data on changing network resources and operations. You receive a complete contextual foundation for making educated selections. In addition to offering a broad range of intelligence, FMC provides a high level of detail, which includes:

  • Trends and high-level statistics are provided. This data assists you in understanding your security posture at any given time, as well as how it is changing, for better or worse.
  • Event specifics, compliance, and forensics. These provide insight into what occurred during a security occurrence. They aid in the improvement of defenses, the containment of breaches, and legal enforcement actions.
  • Workflow information. This data can be simply exported to other platforms to better incident response management.
  • Monitor the health of your device in real-time. Quickly determine the status.

5. FireMon

FireMon solves the complex and dynamic needs of modern company networks by providing real-time visibility and management over security technologies. Web-based KPI dashboards allow network security administrators and security analysts to govern security while optimizing network device configurations.

FireMon addresses three major issues: clean-up, compliance, and change. It examines firewall setups, evaluates policies for administrative regulations, and alerts when network access changes.


Figure 4. Firemon

With a contextual approach, this platform is focused on monitoring and managing network security devices. Its most notable function is traffic flow analysis, which gives consumers detailed reports on network data flow.

  • FireMon Automation provides a comprehensive blueprint for security process automation that speeds up and simplifies policy management through trusted accuracy, gold standards, and proactive continuous compliance.
  • From a single pane of glass, the Security Manager delivers real-time visibility, control, and management for network security devices across hybrid cloud environments.
  • Policy Planner provides intelligent, automated workflow and provisioning, allowing network security and operations teams to apply the necessary modifications with pinpoint accuracy across the rule lifecycle.
  • To maximize performance and assure continued compliance with internal and external standards, Policy Optimizer automates the change review process and streamlines rule justification and clean-up operations.
  • Lumeta is real-time visibility, vulnerability, and risk management system that helps cloud, network, and security teams discover and secure unknown, rogue, and shadow clouds, network infrastructure, and endpoints.
  • Risk Analyzer provides best-in-class vulnerability management by using real-time risk analysis and threat modeling to identify vulnerabilities, rate network risk, and prioritize fixes.

6. ManageEngine Firewall Analyzer

ManageEngine Firewall Analyzer is a program for managing logs, policies, and configurations. It provides configuration monitoring via CLI and API. For security and traffic analysis, it supports the Telnet, SSH, and SCP protocols. It also assists security administrators in tracking policy changes, optimizing firewall performance, and adhering to compliance standards.

  • Aids in the management and optimization of firewall policies
  • Automates the management of firewall rules
  • Tracks config and rule changes
  • Allows you to schedule configuration backups
  • Regular audit compliance inspections are carried out.
  • Conducts regular security audits
  • Notifies you of security occurrences in real-time.
  • Tracks VPN usage and creates VPN statistics Displays firewall security status
  • Monitors employee internet usage.
  • Monitors bandwidth usage and sends alarms when it is exceeded.
  • Firewall logs are collected, consolidated, and analyzed.

Firewall Analyzer supports more than 50 vendors such as Check Point, Paloalto, Cisco Fortinet, Juniper, Sonicwall, WatchGuard, Huawei, pfSense, Cyberoam, Sophos, and more.

Increase your understanding of firewall rules. In your firewall, detect and record redundancy, generalization, correlation, shadow, and grouping anomalies. Learn how to increase performance by rearranging the rules and removing too-permissive rules. Automate firewall rule administration and decide whether a new rule will have a detrimental influence on the existing ruleset.

Detect security breaches, malware, and other irregularities in your network. To identify dangers, do forensic analysis. Know which infections are active on your network, as well as which hosts are afflicted. Use the powerful search features to easily mine the raw firewall logs for security occurrences.

View the full history of all changes made to your firewall configurations. Find out who made what modifications, when they were made, and why. Receive real-time updates on your mobile device. Ensure that all configuration changes made to your firewall device are recorded and that backups are scheduled on a regular basis.

Firewall Analyzer generates comprehensive reports on traffic, protocol usage, web usage, mail usage, FTP usage, Telnet usage, streaming & chat, event summary, VPN, firewall rules, change management, intranet, internet, security, attack, spam, protocol trend, traffic trend, VPN trend, inbound & outbound traffic.

Ensure continuous compliance by automating firewall audit reports. Get reports on regulatory mandates like PCI-DSS, ISO 27001, NIST, SANS, NERC-CIP, SOX, HIPAA, and GDPR right away. With security audit reports, you may assess the impact and severity of vulnerabilities.

Keep an eye out for internal risks by analyzing and identifying the individuals who are responsible, the websites visited, and the websites that exposed the network to attacks. Monitor VPN activity and usage, identify excessive bandwidth usage, trace destination URLs, and prevent undesirable traffic.

7. AlgoSec

Today's enterprise networks are often comprised of a mix of traditional firewalls, next generation firewalls (NGFWs), and cloud-based security controls from various vendors. Each vendor's skills and technological nuances range tremendously, yet you must somehow manage this all together to ensure that your business apps perform properly while maintaining your security posture.


Figure 5. AlgoSec

To provide unified security policy management through a single pane of glass, AlgoSec effortlessly connects with all top brands of classic and next generation firewalls and cloud security controls, as well as routers, load balancers, and web proxies. AlgoSec abstracts vendor-specific technologies, allowing you to focus on what matters most to your organization. AlgoSec streamlines and automates firewall management across your heterogeneous environment, from auto-discovering application connectivity requirements to "zero-touch" change execution and unified risk and compliance reports.

With AlgoSec you can;

  • Get a real-time, intelligent topology map of your whole network security estate.
  • Automate the complete firewall change management process, including hands-free policy push to devices.
  • Along with classic firewalls, manage next-generation firewall policies and cloud security groups.
  • Identify and resolve network connectivity issues
  • Assess risk and optimize firewall rulesets on a regular basis.
  • Generate audit-ready reports for all main regulations in real-time (PCI-DSS, SOX, HIPAA, and many more)

Some of the major benefits of AlgoSec Firewall Management provides are as follows:

  • Manage your entire firewall estate with a single pane of glass.
  • Changes to the process firewall are made in minutes rather than days.
  • Provide a policy that is optimal and secure.
  • Streamline audit preparation procedures and assure ongoing compliance.
  • Avoid disruptions and cyber-attacks caused by misconfigured firewalls.

8. Tufin SecureTrack

Tufin SecureTrack helps enterprises to gain vendor-agnostic, end-to-end visibility, as well as define and manage correct segmentation policies throughout the hybrid cloud environment, in order to limit risk and avoid lateral movement. Regardless of network architecture or cloud platform, SecureTrack provides a real-time hybrid network topology map and segmentation policy orchestration. Segmentation/micro-segmentation policies are developed based on real-time visibility into application/workload communication flows, and are enforced using enforcement points (e.g., firewalls, cloud-native firewalls, etc.) that are currently installed throughout the hybrid environment. Policy creation does not necessitate a thorough understanding of the network capabilities of various firewalls, nor does it necessitate the use of extra agents or proxies.

Tufin SecureTrack

Figure 6. Tufin SecureTrack

Key Features of Tufin SecureTrack are as follows:

  • Real-time Topology Map Across the Hybrid Cloud: SecureTrack discovers a company's network topology and displays it to administrators in the form of a dynamic, visual map. To generate an accurate topology view, connect to all network security devices and infrastructure components, such as multi-vendor firewalls, routers, NGFWs, SDNs, and cloud services, retrieve all routing tables, and examine common network technologies, such as IPSec VPN, MPLS, NAT, and others.
  • Segmentation Policy Generation and Management: Users can define the intended state of security with Tufin SecureTrack by creating a baseline of allowed and restricted communication between security segments and applying it across the hybrid network.

A dashboard view offers a summary of the rule modifications and identifies hazards such as access anomalies, policy violations, and compliance violations that are detected and highlighted, allowing for end-to-end visibility of the hybrid environment's security posture.

  • Policy Optimization and Clean up: SecureTrack assists in the development of least privilege policies. SecureTrack finds too permissive rules and how to reduce them using Tufin's Automated Policy Generator (APG) in order to improve rules based on real behavior. The APG assures minimum privilege compliance while maintaining connectivity.
  • Real-time Monitoring and Alerts: Tufin SecureTrack gives information and visibility into rule utilization and trigger rates to assist in policy optimization. Tufin automatically discovers and indicates unused, hidden, redundant, and too permissive rules for quick remediation.
  • Troubleshooting Connectivity: Network and security professionals can rapidly and accurately investigate and fix network disruptions throughout the multi-vendor, hybrid environment, and properly plan connectivity upgrades, thanks to SecureTrack's accurate topology modeling and path analysis.
  • Auditing and Continuous Compliance: SecureTrack provides established compliance segmentation policy templates against which all rules can be checked to ensure compliance with industry standards. SecureTrack also delivers automatic audit reports that compare current firewall configuration to corporate security policy, as well as a standards checklist that may be customized.

Tufin SecureTrack provides benefits to its users such as;

  • Set and maintain policies for segmentation or micro-segmentation across the hybrid cloud, regardless of the underlying architecture.
  • Detect access violations and mitigate risk rapidly by utilizing accurate topology and policy data, independent of infrastructure.
  • Utilize automated policy generation and path analysis to optimize policies and vet access modifications.
  • Achieve complete insight across on-premise and hybrid cloud environments; and Enable continuous compliance with real-time monitoring and notifications for policy violations and regulatory compliance issues.
  • Ensure continual compliance with laws such as PCI-DSS, SOX, NERC CIP, and others by maintaining audit readiness with a fully documented audit trail.

9. Firewall Browser

SolarWinds Firewall Browser allows IT workers to troubleshoot firewalls and manage change requests from the comfort of their PC. This free tool alleviates the difficulties associated with ruleset searches based on address or service ranges, which is how change requests are typically submitted. SolarWinds Firewall Browser is the only free firewall configuration search tool that allows you to conduct limitless searches on mixed-vendor inventory from a single, easy-to-use interface.

Some of the functions of Firewall Browser are listed below:

  • Import and search for an unlimited number of Cisco, Check Point, and Netscreen setups.
  • Search for rules and objects using an IP address, a name, a service, or a port number.
  • Check to see if a change request has previously been handled by the security rules.
  • Determine the appropriate rules and objects that can be reused to effect change.
  • Analyze the effect of a change on an object group.

10. Palo Alto Panorama

Panorama is a security management solution that enforces consistent policies in a dynamic network and threat scenario. Manage your network security with a single security rule base that includes firewalls, threat prevention, URL filtering, application awareness, user identification, sandboxing, file blocking, access control, and data filtering. This critical simplicity, along with App-IDTM technology-based rules, dynamic security upgrades, and rule usage analysis, minimizes administrative workload while improving overall security posture.

Panorama allows you to manage your Palo Alto Networks firewalls using a methodology that offers both global and regional control. Panorama includes a variety of options for global or centralized administration.

Panorama considers enterprise users. From a single console, you can manage your internet edge as well as your private and public cloud deployments. Panorama provides continuous visibility and administration of north-south and east-west traffic, regardless of whether it is hosted on-premises or in the cloud. It centrally manages all groups of firewalls' devices and security configurations across all form factors (physical, virtual, cloud-delivered, and containerized). Panorama can be deployed using virtual appliances, purpose-built appliances, or a hybrid of the two.

Palo Alto Panorama

Figure 7. Palo Alto Panorama

Key Features of Panorama are as follows:


  • Device groups, hierarchies, and tags for policy organization

  • Template stacks for reusable network setup

  • Administrator-specific commits to prevent unintentional changes

  • SD-WAN connectivity for branch offices

  • Zero-touch provisioning (ZTP) to ease firewall onboarding and provisioning at remote sites


  • Centralized visibility throughout the infrastructure

  • Actionable insights

  • Health profiling for a better knowledge of device usage


  • Simple conversion of traditional rules to application-based rules utilizing PAN-OS® intelligence

  • Rule use analysis to lower the attack surface and improve security posture


  • Log filtering and automatic actions on third-party systems

  • Policy deployments for dynamic environments

  • XML and JSON-based REST APIs for simple integration

  • Centralized distribution of the most recent security content changes.

What are Best Practices for Firewall Management?

Because a variety of factors influence your company's network, security, and system activities, managing, configuring, and troubleshooting your firewall may be more difficult than it appears. Proper firewall management by network managers ensures that the IT infrastructure is protected and safe from threatening traffic from outside the network as well as illegal traffic. Here are a few best practices for firewall management that may be of assistance.

  • Schedule regular firewall security audits.
  • Apply NAC (Network Access Control).
  • Ensure that the firewall software is kept up to date.
  • Prepare a firewall change management strategy.
  • Examine the effects of firewall policy modifications.
  • Update and maintain your firewall rule base

How to Manage Firewall?

The firewall, from the standpoint of the small office/home user, is a single device that protects the home network from harmful traffic - it keeps out the "bad stuff" and gives the end-user a more safe online experience. Depending on how the security policy calls for enforcing the edge network, the firewall for the enterprise can be both an inbound and outbound filter. In any event, the firewall (or, in the case of organizations, firewalls) must be managed in some way.

Nowadays, most manufacturers rely on a web interface. This is due to the notion that a graphical user interface (GUI) is more natural to the end-user and thus presumably easier to use than a command-line interface in the home market (CLI). However, for the more courageous among us, there are firewalls (such as the PIX, Linux IPTables, and Solaris IPF, to mention a few) that can be managed entirely from the CLI.

This section presents default passwords, the maintenance of the underlying firewall platform for firewalls, and administering firewalls via the CLI and a GUI and common firewall management tasks.

  • Default Passwords: When you buy a new firewall, it comes with a default configuration. This is because the manufacturer must offer the end-user initial access to the device in order for it to be configured. Most recent documentation for any device admonishes the end-user to immediately change the default password to something else.
  • Maintaining the Underlying Platform: To accomplish their tasks, firewalls, like any other network device, use software (whether embedded in an application-specific integrated circuit [ASIC], runs from Flash memory, or operates from a disk file system). Typically, like with the Cisco PIX and ASA platforms, as well as NetScreen and other vendor firewalls, these firewalls run a bespoke operating system whose source code is not available for study or modification by the general public. If an outside party discovers a bug or vulnerability, it is up to the manufacturer to create a patch and distribute a new version of the operating system for the end-user to install in order to remedy the problem. It takes time to maintain the underlying platform. The more complicated the underlying platform, the longer it takes.
  • Using a CLI to Manage Firewalls: A CLI allows you to configure the firewall by using a specific instruction set. Most firewalls need the end-user to configure the firewall through CLI (inputting basic network information such as IP address, netmask, default gateway, and potentially an administrative password) before switching to the GUI.
  • Using a Graphical User Interface to Manage Firewalls: A graphical user interface (GUI) provides a more user-friendly interface for configuring the firewall. Some firewalls are configured using a host-side direct interface.
  • Interface Preference: Management of a firewall can range from highly complex to reasonably simple, depending on whether it is done using a CLI or a GUI. In most cases, inexperienced users begin by administering the firewall via a graphical user interface (GUI). As their level of familiarity and comfort with the firewall grows, they may find it more convenient to use a CLI. One big advantage of a CLI over a GUI is that the CLI may be accessed via Telnet and SSH sessions, as well as by connecting directly to the serial port.
  • Management Access: Controlling access to network infrastructure devices' management interfaces is crucial. Only those people who need to administer network devices such as routers, switches, intrusion detection systems, and firewalls should have access to them. This requirement derives from the fact that an unauthorized user, whether malevolent or not, has the ability to change the settings or disable the device, lowering the security of the surrounding network. Management access is available in two flavors: in-band and out-of-band. There are a few other things to think about when it comes to how the firewall is accessed: Telnet, SSH, SNMP, FTP, TFTP, HTTP/HTTPS, or a proprietary management protocol are all options.
  • In-Band Management: In-band management refers to administrative access to systems and network devices via the same network that the filtered traffic uses. If certain safeguards are not taken, in-band administration might pose a substantial risk to the administrator. These dangers are primarily associated with the use of unencrypted communication methods. When deciding whether to run a firewall in-band, special consideration must be given to the use of encrypted communications such as SSH and HTTPS. The usage of simple Telnet or HTTP can result in an attacker capturing the administrative password while sniffing the traffic between the firewall's administrative interface and the rest of the network.
  • Out-of-Band Management: Out-of-band management, as the name implies, involves gaining access to the firewall via a secondary route that is not carrying production traffic. This can be a VLAN configured for administrative access to network devices and hosts, or it can be a whole different physical network. Furthermore, out-of-band management can be utilized to enable access to the network device's serial port in the event that the network fails. Out-of-band administration is more time-consuming to set up and less cost-effective for smaller networks, but it is the most secure and dependable means of managing firewalls and other network devices.
  • Common Tasks Associated with Firewall Administration: When implementing a new firewall, whether for an enterprise deployment or a deployment in a small office or home office, one of the first tasks is to configure some basic networking characteristics. Changing the default administrator password, configuring the default gateway, configuring the IP addresses for the internal and external (and perhaps other) interfaces, and configuring message logging from the firewall are all part of this process. In addition to these activities, the firewall administrator must manage the firewall's configuration over time. This may need the use of a change control system, such as the Revision Control System (RCS), which is available on both the UNIX/Linux and Windows platforms.