Welcome!

Microservices Expo Authors: Elizabeth White, Pat Romanski, Liz McMillan, Olivier Huynh Van, Gregor Petri

Related Topics: Cloud Security, Microservices Expo, Containers Expo Blog, @CloudExpo

Cloud Security: Article

Top Ten Firewall Management Metrics that Matter…and Why

Proper attention to these metrics will keep your firewalls optimized

If you look at some of the headline-making breaches of the past few years, they all occurred at large companies with highly dynamic and complex computing environments. Securing these environments is impossible to do without automation, which is why so much of the innovation in IT security in recent years has been focused on automating security management.

Network security is one area where systems have become too complex to manage manually. Let's take firewalls as a case in point. A single firewall can have hundreds or thousands of rules, each made up of three components: source, destination and service. Next-generation firewalls add at least two additional fields - users and applications.

Larger companies have hundreds of firewalls, usually from multiple vendors, in multiple geographies, managed by different people. That's just for starters - any number of factors can exponentially increase the degree of firewall complexity. While rare, in extreme situations a particularly bloated or neglected rule base - or even a simple typo while configuring a rule - if left untended, can result in a situation where a firewall can introduce more risk than it prevents.

The only way to get your brain around the state of your firewalls is to audit them. While manual audits can be painful (not to mention error prone), it may be the best way to fast-track proper firewall management. Regardless of whether an audit is manual or automated, here are some important metrics to look for:

  1. Number of shadowed or redundant rules: Shadowed rules refer to rules that are masked, completely or partially, by other rules that are either placed higher up in the rule base. Shadowed rules are very common because administrators add new firewall rules all the time but for a variety of reasons - fear of causing an outage, or not knowing why a rule was added in the first place - rarely delete them. A rule base filled with shadowed rules is not only inefficient, it puts a much greater strain on the firewall then is necessary, which can lead to performance issues.
  2. Number of unused rules: Unused rules will appear rarely, if at all, in firewall logs because they aren't being used for legitimate traffic. Unused rules can lead to serious exposures, such as allowing access to a server that is no longer being used and, as a result, exposing a service likely not properly patched. Looking for unused rules manually can be an extremely slow and tedious process, which is why admins hate to do it. However, automated solutions can make auditing for unused rules both manageable and simple.
  3. Number of unused objects: An object is a component of a rule, and a single field of a rule (i.e., source, destination or service) can have multiple objects - such as a business unit having access to multiple destinations and/or services. Not only do unused objects appear much more frequently than unused rules, they are that much harder to find manually. Cleaning up unused objects can significantly tighten up a rule base and often lead to improved performance.
  4. Number of rules with permissive services: The most common examples of this are rules with "ANY " in the service field, but in general, permissive services give more access then is needed to the destination by allowing additional services (which are often applications), which can lead to unauthorized use, allow the service to be a springboard to other parts of the network, or leave it exposed to malicious activity.
  5. Number of rules with risky services (such as telnet, ftp, snmp, pop, etc.) in general or between zones (i.e., between Internal, DMZ, External, or between development and production networks): Risky services are deemed risky because they usually allow credentials to be passed in plain text, often contain sensitive info or enable access to sensitive systems. Any service that exposes sensitive data or allows for shell access should be tightly monitored and controlled.
  6. Number of expired rules: Any rule that was created on a temporary basis and has clearly expired is just taking up space and does not need to remain in the rule base. If there is no documentation as to when or why the rule expired, check the firewall logs for its "hit count" (or usage, in firewall management-speak).
  7. Number of unauthorized changes: These are rules that are not associated with a specific change ticket. In order to ensure all requests are properly handled, all requests, from initial request to final implementation, and should be managed via a ticketing system. If a change causes a problem and no one has any clue why the change was made, who made it, whether it was assessed for compliance and/or security risk, who approved, etc., it results in a huge waste of resources, and is a clear indicator that firewall management processes are inefficient.
  8. Percentage of changes made outside of authorized change windows: Outages in IT are usually caused by the work IT does. In order to minimize business disruption, change windows are usually set during times when the least amount of people are on the network - for example, firewall admins like to implement rule changes late at night, usually on the weekends. That way, if there is an outage it is much easier to track which change caused it and how. If the majority of changes are made outside of normal change windows, it is usually because admins are spending too much time putting out fires, which indicates the firewall management processes are in need of an overhaul.
  9. Number of rules with no documentation: While the comments section of a firewall rule has text limits that inhibit proper documentation, all change tickets have a comments section, which can be used to provide a business justification for the rule. Some people use spreadsheets to capture this information although using a spreadsheet as a central repository for change information leads to the same issues as with other manual processes. Without proper documentation there is no way to know why a rule was implemented and if it is still necessary.
  10. Number of rules with no logging: Proper firewall management is impossible without leveraging the data found in firewall logs. Similar to other areas of IT, there was a resistance to turning on logging because it would cause performance issues. However, firewall (and firewall management) technology has evolved to the point where logging no longer impacts performance. If there are performance issues with your firewalls, than something else in your environment is not optimal. Determining rule and object usage (numbers two and three in this list) are impossible to do without logging, as is proper forensics and troubleshooting. The advent of automated tools for firewall management makes scanning logs for relevant data a highly manageable endeavor.

Plenty of lip service has been given to the credo that good IT is a function of people, process and technology. Given the fast pace of modern business, breakdowns are bound to happen, and unless a company decides to not use the Internet, they will always be facing a certain level of exposure. While there will never be silver bullet for security, the good news is that proper attention to the metrics above will keep your firewalls optimized so that they remain one of your strongest and most reliable security assets and not a potential liability.

More Stories By Michael Hamelin

Michael Hamelin is Chief Security Architect at Tufin Technologies where he identifies and champions the security standards and processes for Tufin. Bringing more than 16 years of security domain expertise to Tufin, Hamelin has deep hands-on technical knowledge in security architecture, penetration testing, intrusion detection, and anomalous detection of rogue traffic. He has authored numerous courses in information security and worked as a consultant, security analyst, forensics lead, and security practice manager. He is also a featured security speaker around the world widely regarded as a leading technical thinker in information security.

Hamelin previously held technical leadership positions at VeriSign, Cox Communications, and Resilience. Prior to joining Tufin he was the Principal Network and Security Architect for ChoicePoint, a LexisNexis Company. Hamelin received BS degrees in Chemistry and Physics from Norwich University, and did his graduate work at Texas A&M University.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


@MicroservicesExpo Stories
Your business relies on your applications and your employees to stay in business. Whether you develop apps or manage business critical apps that help fuel your business, what happens when users experience sluggish performance? You and all technical teams across the organization – application, network, operations, among others, as well as, those outside the organization, like ISPs and third-party providers – are called in to solve the problem.
Enterprise IT has been in the era of Hybrid Cloud for some time now. But it seems most conversations about Hybrid are focused on integrating AWS, Microsoft Azure, or Google ECM into existing on-premises systems. Where is all the Private Cloud? What do technology providers need to do to make their offerings more compelling? How should enterprise IT executives and buyers define their focus, needs, and roadmap, and communicate that clearly to the providers?
SYS-CON Events announced today that Commvault, a global leader in enterprise data protection and information management, has been named “Bronze Sponsor” of SYS-CON's 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Commvault is a leading provider of data protection and information management solutions, helping companies worldwide activate their data to drive more value and business insight and to transform moder...
Much of the value of DevOps comes from a (renewed) focus on measurement, sharing, and continuous feedback loops. In increasingly complex DevOps workflows and environments, and especially in larger, regulated, or more crystallized organizations, these core concepts become even more critical. In his session at @DevOpsSummit at 18th Cloud Expo, Andi Mann, Chief Technology Advocate at Splunk, showed how, by focusing on 'metrics that matter,' you can provide objective, transparent, and meaningful f...
There is little doubt that Big Data solutions will have an increasing role in the Enterprise IT mainstream over time. Big Data at Cloud Expo - to be held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA - has announced its Call for Papers is open. Cloud computing is being adopted in one form or another by 94% of enterprises today. Tens of billions of new devices are being connected to The Internet of Things. And Big Data is driving this bus. An exponential increase is...
The many IoT deployments around the world are busy integrating smart devices and sensors into their enterprise IT infrastructures. Yet all of this technology – and there are an amazing number of choices – is of no use without the software to gather, communicate, and analyze the new data flows. Without software, there is no IT. In this power panel at @ThingsExpo, moderated by Conference Chair Roger Strukhoff, panelists will look at the protocols that communicate data and the emerging data analy...
DevOps at Cloud Expo, taking place Nov 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 19th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to wait for long dev...
SYS-CON Events announced today that Tintri Inc., a leading producer of VM-aware storage (VAS) for virtualization and cloud environments, will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Tintri VM-aware storage is the simplest for virtualized applications and cloud. Organizations including GE, Toyota, United Healthcare, NASA and 6 of the Fortune 15 have said “No to LUNs.” With Tintri they mana...
All clouds are not equal. To succeed in a DevOps context, organizations should plan to develop/deploy apps across a choice of on-premise and public clouds simultaneously depending on the business needs. This is where the concept of the Lean Cloud comes in - resting on the idea that you often need to relocate your app modules over their life cycles for both innovation and operational efficiency in the cloud. In his session at @DevOpsSummit at19th Cloud Expo, Valentin (Val) Bercovici, CTO of So...
SYS-CON Events announced today the Enterprise IoT Bootcamp, being held November 1-2, 2016, in conjunction with 19th Cloud Expo | @ThingsExpo at the Santa Clara Convention Center in Santa Clara, CA. Combined with real-world scenarios and use cases, the Enterprise IoT Bootcamp is not just based on presentations but with hands-on demos and detailed walkthroughs. We will introduce you to a variety of real world use cases prototyped using Arduino, Raspberry Pi, BeagleBone, Spark, and Intel Edison. Y...
Video experiences should be unique and exciting! But that doesn’t mean you need to patch all the pieces yourself. Users demand rich and engaging experiences and new ways to connect with you. But creating robust video applications at scale can be complicated, time-consuming and expensive. In his session at @ThingsExpo, Zohar Babin, Vice President of Platform, Ecosystem and Community at Kaltura, will discuss how VPaaS enables you to move fast, creating scalable video experiences that reach your...
DevOps at Cloud Expo – being held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA – announces that its Call for Papers is open. Born out of proven success in agile development, cloud computing, and process automation, DevOps is a macro trend you cannot afford to miss. From showcase success stories from early adopters and web-scale businesses, DevOps is expanding to organizations of all sizes, including the world's largest enterprises – and delivering real results. Am...
Large enterprises today are juggling an enormous variety of network equipment. Business users are asking for specific network throughput guarantees when it comes to their critical applications, legal departments require compliance with mandated regulatory frameworks, and operations are asked to do more with shrinking budgets. All these requirements do not easily align with existing network architectures; hence, network operators are continuously faced with a slew of granular parameter change req...
About a year ago we tuned into “the need for speed” and how a concept like "serverless computing” was increasingly catering to this. We are now a year further and the term “serverless” is taking on unexpected proportions. With some even seeing it as the successor to cloud in general or at least as a successor to the clouds’ poorer cousin in terms of revenue, hype and adoption: PaaS. The question we need to ask is whether this constitutes an example of Hype Hopping: to effortlessly pivot to the ...
If you’re responsible for an application that depends on the data or functionality of various IoT endpoints – either sensors or devices – your brand reputation depends on the security, reliability, and compliance of its many integrated parts. If your application fails to deliver the expected business results, your customers and partners won't care if that failure stems from the code you developed or from a component that you integrated. What can you do to ensure that the endpoints work as expect...
Digitization is driving a fundamental change in society that is transforming the way businesses work with their customers, their supply chains and their people. Digital transformation leverages DevOps best practices, such as Agile Parallel Development, Continuous Delivery and Agile Operations to capitalize on opportunities and create competitive differentiation in the application economy. However, information security has been notably absent from the DevOps movement. Speed doesn’t have to negat...
With the rise of Docker, Kubernetes, and other container technologies, the growth of microservices has skyrocketed among dev teams looking to innovate on a faster release cycle. This has enabled teams to finally realize their DevOps goals to ship and iterate quickly in a continuous delivery model. Why containers are growing in popularity is no surprise — they’re extremely easy to spin up or down, but come with an unforeseen issue. However, without the right foresight, DevOps and IT teams may lo...
As applications are promoted from the development environment to the CI or the QA environment and then into the production environment, it is very common for the configuration settings to be changed as the code is promoted. For example, the settings for the database connection pools are typically lower in development environment than the QA/Load Testing environment. The primary reason for the existence of the configuration setting differences is to enhance application performance. However, occas...
Information technology is an industry that has always experienced change, and the dramatic change sweeping across the industry today could not be truthfully described as the first time we've seen such widespread change impacting customer investments. However, the rate of the change, and the potential outcomes from today's digital transformation has the distinct potential to separate the industry into two camps: Organizations that see the change coming, embrace it, and successful leverage it; and...
While DevOps promises a better and tighter integration among an organization’s development and operation teams and transforms an application life cycle into a continual deployment, Chef and Azure together provides a speedy, cost-effective and highly scalable vehicle for realizing the business values of this transformation. In his session at @DevOpsSummit at 19th Cloud Expo, Yung Chou, a Technology Evangelist at Microsoft, will present a unique opportunity to witness how Chef and Azure work tog...