Cisco IOS Security vs Zscaler Cloud Firewall comparison

Cisco and Zscaler are both solutions in the Firewalls category. Cisco is ranked #29 with an average rating of 9.0, while Zscaler is ranked #36 with an average rating of 7.5. Cisco holds a 0.4% mindshare in Firewalls, compared to Zscaler’s 0.6% mindshare. Additionally, 91% of Cisco users are willing to recommend the solution, compared to 93% of Zscaler users who would recommend it.

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Executive SummaryUpdated on Sep 16, 2024

Cisco IOS Security and Zscaler Cloud Firewall compete in the network security market. Zscaler Cloud Firewall seems to have the upper hand due to its cloud-native approach and advanced threat intelligence.

Features: Cisco IOS Security is noted for advanced routing, secure network protocols, and VPN capabilities. Zscaler Cloud Firewall is recognized for deep SSL inspection, real-time threat detection, and scalability.

Room for Improvement: Cisco IOS Security could benefit from more intuitive management tools, simplified policy configuration, and better integration with modern systems. Zscaler Cloud Firewall needs improvements in reporting capabilities, integration with legacy systems, and enhanced user training resources.

Ease of Deployment and Customer Service: Deployment of Cisco IOS Security is complex, requiring specialized skills and hardware, but it is backed by comprehensive customer support. Zscaler Cloud Firewall offers streamlined deployment thanks to its cloud-based architecture, with responsive customer service, although it may lack the depth of Cisco's support.

Pricing and ROI: Cisco IOS Security involves significant upfront costs for hardware and licensing, offering good ROI but with high initial investment. Zscaler Cloud Firewall's subscription-based pricing model is more flexible and cost-effective long-term, delivering strong ROI through reduced maintenance costs and improved operational efficiency.

To learn more, read our detailed Cisco IOS Security vs. Zscaler Cloud Firewall Report (Updated: December 2025).

Buyer's Guide

Cisco IOS Security vs. Zscaler Cloud Firewall

December 2025

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Helped 881,114 peers since 2012

Review summaries and opinions

We asked business professionals to review the solutions they use. Here are some excerpts of what they said:

ROI

Sentiment score

5.8

Fortinet FortiGate offers cost-effective, robust security, reducing expenses, enhancing efficiency, easy implementation, quick ROI, and improved network management.

Sentiment score

7.4

Cisco IOS Security delivered significant ROI through improved routing, security, stability, and cost-efficiency, despite competitive vendor pressures.

Sentiment score

1.0

Users experienced cost reductions, improved security, enhanced performance, easier scalability, better threat protection, simplified management, and efficient resource utilization.

Clients are now comfortable and not wasting productive hours on IT support.

MURALI NIDAMANURI

Managing Director at a manufacturing company with 10,001+ employees

The automation part is giving us a cost benefit and speed; we can react faster.

Bart Homblé

BDM Fortinet & BDM Teamlead at Exclusive Networks

It's a very useful tool to mitigate and protect your enterprise.

Bernard Samontanes

Staff Infrastructure & Security Engineer at Mozn Systems

For more quotes and insights, download the Fortinet FortiGate report

The return on investment is satisfactory with Cisco products as they have long lifespans, and our customers are satisfied with them.

Danijel Cerovecki

Head of Cyber Defense Department and Network Technologies Department at Verso Altima

For more quotes and insights, download the Cisco IOS Security report

No quotes available

For more quotes and insights, download the Zscaler Cloud Firewall report

Customer Service

Sentiment score

6.6

Fortinet FortiGate's customer service is generally praised for responsiveness, though some users experience delays in critical situations.

Sentiment score

6.7

Cisco IOS Security support is generally praised for speed and skill, though some report delays and complexity in access.

Sentiment score

5.0

Zscaler Cloud Firewall offers responsive and knowledgeable support, though occasional escalations might cause delays, with room for improvement.

The quick resolution of issues with Fortinet FortiGate is due to the support of the company and the fact that the equipment is easy to work with.

Alexandre Menezes

IT Manager at a consultancy with 10,001+ employees

I would rate the technical support for Fortinet FortiGate a ten out of ten.

AnishKumar

NAC Support at Rah Infotech Pvt Ltd

As a solution provider, when I encounter problems, I connect directly with Fortinet support, and they provide solutions within a very short time.

Vasu Gala

Manager, Information Technology Operation/Presales at TechMonarch

For more quotes and insights, download the Fortinet FortiGate report

My impression is that the support quality has deteriorated over time.

Danijel Cerovecki

Head of Cyber Defense Department and Network Technologies Department at Verso Altima

For more quotes and insights, download the Cisco IOS Security report

The response and support are sometimes inadequate, which detracts from the overall experience of an otherwise impressive solution.

Carlos Snel

Director at Aquila ICT Solutions

The technical support from Zscaler was excellent.

KashyapGhotane

Cyber Security Architect at Accenture

For more quotes and insights, download the Zscaler Cloud Firewall report

Scalability Issues

Sentiment score

7.1

Fortinet FortiGate is scalable and popular for SMEs but requires careful design and may incur scaling costs and licensing constraints.

Sentiment score

7.4

Cisco IOS Security offers scalable, enterprise-level solutions but may increase costs and limit universality due to required hardware.

Sentiment score

5.3

Zscaler Cloud Firewall is scalable and easy to manage, praised for performance and user satisfaction across various regions.

They scale up really well from smaller models like the FortiGate 40 and 50 to bigger sites with the FortiGate 100 for more throughput - up to enterprise datacenters.

Ian Manton

IT Manager at Daltons Limited

The variation comes in terms of the interfaces and throughputs, but from a security perspective, you get the same benefit, irrespective of whether you have an entry-level unit or an enterprise.

reviewer2667480

Cewa Solutions Architect at a tech services company with 11-50 employees

We determine sizing based on multiple factors: number of users, available links, traffic types, server count, services in use, and whether services will be published.

FatmaSamy

General Surgery Specialist at Helwan University Cairo

For more quotes and insights, download the Fortinet FortiGate report

No quotes available

For more quotes and insights, download the Cisco IOS Security report

In this case, Twingate will be very easy compared to Zscaler.

reviewer2641644

IT Security at a manufacturing company with 11-50 employees

For more quotes and insights, download the Zscaler Cloud Firewall report

Stability Issues

Sentiment score

7.7

Fortinet FortiGate is praised for its stability, with effective long-term performance and improvements in newer firmware versions.

Sentiment score

7.6

Cisco IOS Security is generally reliable with occasional issues, frequently updated for stability, scoring 7-10 in satisfaction.

Sentiment score

6.4

Zscaler Cloud Firewall is stable, reliable, and well-rated, with minor performance issues and redundancy minimizing outages.

We're experiencing 99.999% availability consistently.

Ricardo Biggs

Manager, Information Technology at a consumer goods company with 11-50 employees

I would rate the stability of Fortinet FortiGate a ten out of ten.

AnishKumar

NAC Support at Rah Infotech Pvt Ltd

Currently, we are experiencing a general outage of one of the main internet service providers of the Dominican Republic, and we have not been impacted in our operations because with SD-WAN, we have another internet service provider and we are working with the second WAN connection without any disruption.

Juan Frias

CISO at a financial services firm with 1,001-5,000 employees

For more quotes and insights, download the Fortinet FortiGate report

We find Cisco products stable and thoroughly tested before new software or firmware versions are released.

Danijel Cerovecki

Head of Cyber Defense Department and Network Technologies Department at Verso Altima

I find Cisco IOS Security to be a very stable product.

Binoob John

Partner/Owner and Director of Human Resources at Up arrow Systems

For more quotes and insights, download the Cisco IOS Security report

There were some stability issues due to occasional latency and lags, particularly with the GUI and report generation.

KashyapGhotane

Cyber Security Architect at Accenture

For more quotes and insights, download the Zscaler Cloud Firewall report

Room For Improvement

Fortinet FortiGate needs enhanced UI, simplified licensing, improved performance, reporting, third-party integration, and expanded automation features.

Cisco IOS Security struggles with integration, usability, cost, lacking features, complex licensing, performance, and requires enhancement and support.

Zscaler Cloud Firewall needs improved features, better integration, enhanced support, wider coverage, affordable pricing, and a modernized interface.

These sessions should be around five to ten minutes long, allowing users and partners to quickly grasp the information without disrupting their daily tasks.

MURALI NIDAMANURI

Managing Director at a manufacturing company with 10,001+ employees

The solution should be able to implement machine learning and analytics of all the logs for threat detection and protection.

Elvis Mahadeo

Senior Systems Engineer at Caribbean Development Company

It would be better for customers to get immediate replacements even with a standard subscription.

Pravin Mandlik

Director at a tech services company with 11-50 employees

For more quotes and insights, download the Fortinet FortiGate report

Cisco changes their licensing policy quite frequently, which is becoming confusing and complicated.

Danijel Cerovecki

Head of Cyber Defense Department and Network Technologies Department at Verso Altima

For more quotes and insights, download the Cisco IOS Security report

For now, there is no dashboard or network management system available for Twingate.

reviewer2641644

IT Security at a manufacturing company with 11-50 employees

The reverse proxy feature for Data Loss Prevention (DLP) is missing.

KashyapGhotane

Cyber Security Architect at Accenture

I believe the integration of AI could improve the dashboard by making it more agile and effective in monitoring and predicting threats.

Carlos Snel

Director at Aquila ICT Solutions

For more quotes and insights, download the Zscaler Cloud Firewall report

Setup Cost

Enterprise buyers find Fortinet FortiGate costly initially, but cheaper overall, despite some high renewal and setup costs.

Cisco IOS Security is costly, favoring medium to large enterprises with longer-term savings over SMB challenges.

Zscaler Cloud Firewall is flexible yet expensive, valued for tiered packages, with prices affected by user count and features.

Last year, I renewed the support for three years, which can sometimes be expensive but depends on the security benefits and how it helps us.

AiméKouchade

Network & System Admin at Invoke Studios

It offers cost savings as it is generally cheaper than the competition.

NilsPaley

IT Infrastructure Architect at Apotek 1

It is about 20% cheaper.

MithatBulut

Network Security Engineer at TD SYNNEX

For more quotes and insights, download the Fortinet FortiGate report

The cost of Cisco IOS Security for customers is on the higher end of pricing compared to the competition, depending on the targeted customers.

Danijel Cerovecki

Head of Cyber Defense Department and Network Technologies Department at Verso Altima

For more quotes and insights, download the Cisco IOS Security report

Zscaler Cloud Firewall is quite expensive compared to competitors.

KashyapGhotane

Cyber Security Architect at Accenture

For more quotes and insights, download the Zscaler Cloud Firewall report

Valuable Features

Fortinet FortiGate provides robust, flexible security solutions with key features like web filtering, SSL VPN, SD-WAN, and centralized management.

Cisco IOS Security offers scalable, stable solutions with VPN, AAA, firewall integration, and user-friendly management for high-demand environments.

Zscaler Cloud Firewall offers advanced threat protection, simplified management, and seamless integration, enhancing security with flexible policy customization and traffic control.

These features help reduce our downtime, manage the ISPs, and deploy SLAs for all the website traffic.

Syed Ali Waqas

Head IT at Burraq Cyber Security Solutions

The most valuable feature of FortiGate is FortiView which provides proactive monitoring.

Viraj Fernandopulle

General Manager Group IT at DART GLOBAL LOGISTICS PTE. LTD.

We got a firewall and gave an SSL VPN to my client to connect to their servers, after which, such kind of activities involving ransomware attacks stopped.

VINAY GUJARATHI

Owner at Mindware Computer Solutions

For more quotes and insights, download the Fortinet FortiGate report

This solution, called Network Access Controller, handles authentication, authorization, and accounting for devices accessing the network.

Binoob John

Partner/Owner and Director of Human Resources at Up arrow Systems

The best features of Cisco IOS Security are its integration with software management tools such as Cisco DNA Center and Cisco ICE, which provide centralized policy and network access control.

Danijel Cerovecki

Head of Cyber Defense Department and Network Technologies Department at Verso Altima

For more quotes and insights, download the Cisco IOS Security report

It is really customized, a security policy that can be applied to the users so they can access only the resources I enable them.

reviewer2641644

IT Security at a manufacturing company with 11-50 employees

Advanced threat protection features in Zscaler Cloud Firewall are practically the key component that every customer wants.

Carlos Snel

Director at Aquila ICT Solutions

The biggest advantage of Zscaler Cloud Firewall is its consolidation of products.

KashyapGhotane

Cyber Security Architect at Accenture

For more quotes and insights, download the Zscaler Cloud Firewall report

Categories and Ranking

Fortinet FortiGate

Mindshare comparison

As of January 2026, in the Firewalls category, the mindshare of Fortinet FortiGate is 18.8%, down from 20.7% compared to the previous year. The mindshare of Cisco IOS Security is 0.4%, up from 0.2% compared to the previous year. The mindshare of Zscaler Cloud Firewall is 0.6%, up from 0.3% compared to the previous year. It is calculated based on PeerSpot user engagement data.

Firewalls Market Share Distribution
Product	Market Share (%)
Fortinet FortiGate	18.8%
Cisco IOS Security	0.4%
Zscaler Cloud Firewall	0.6%
Other	80.2%

Firewalls

Featured Reviews

Vasu Gala

Manager, Information Technology Operation/Presales at TechMonarch

A stable solution with an intuitive interface and quick customer service

I have been working with Fortinet FortiGate, WatchGuard, Sophos, and SonicWall. I'm not as comfortable with SonicWall because of their UI and limitations. I prefer Fortinet above all other options. When it comes to configuration, I am confident in my ability to handle various tasks, including creating policies such as firewall rules, web policies, and application policies. Additionally, I can configure VPNs and implement load balancing, among other tasks. Overall, I feel much more comfortable working with Fortinet. Fortinet has made significant improvements by integrating AI with firewalls for threat analysis and prevention. In the past 2-3 years, they have launched FortiSASE and SIEM, and they also provide SOC services. Both Palo Alto and Fortinet FortiGate are excellent. While Fortinet FortiGate comes at higher prices, the functionality and support justify the cost. They promptly resolve firmware issues and inform all support providers about configuration changes.

Read full review

Danijel Cerovecki

Head of Cyber Defense Department and Network Technologies Department at Verso Altima

Have faced challenges in keeping licensing clear and consistent while ensuring reliable network protection

We are a Gold Partner with Cisco. Our customers come from various industries, including service providers, and we target service providers and enterprise customers.We do not extensively use Zone-Based Firewalls in Cisco IOS Security, instead typically deploying standalone firewalls such as Cisco FTDs or Cisco ASA devices. For threat analytics and vulnerability scanning, we utilize third-party vendors with dedicated devices and software. We use products such as Tenable from Nessus for this type of analysis. We have implemented Secure Access Control Server in Cisco IOS Security, which combines multiple security mechanisms including AAA, 802.1X for network access control with Cisco ICE, TrustSec for identity-based segmentation, and Cisco DNA Center. Cisco IOS Security's VPN support is comprehensive and increasingly important in daily communication, from basic site-to-site tunnels to remote access VPNs and SD-WAN secure VPNs. Protecting and encrypting communication is essential in modern networks. The challenges with Cisco IOS Security are more operational than product-related. There is an understaffing issue, making automation and orchestration capabilities particularly valuable. For the products themselves, we only encounter routine operational matters such as addressing new vulnerabilities and patching. For those considering Cisco IOS Security, it is important to understand that Cisco offers a complete ecosystem. When embracing the Cisco ecosystem fully, customers receive excellent products and comprehensive solutions. On a scale of 1-10, I rate Cisco IOS Security a 9.

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Carlos Snel

Director at Aquila ICT Solutions

Has streamlined secure deployments across large enterprises while offering reliable protection and intuitive management

The centralized management console, also referred to as the Zscaler dashboard, impacts the ability of my customers to respond to security incidents significantly. I see it as user-friendly, and clients are really happy with using it, which motivates them to keep using Zscaler Cloud Firewall because they enjoy the GUI. It's very intuitive, making it easy to navigate alerts and incidents. My clients rarely have questions about where to find specific information once Zscaler Cloud Firewall is running. The interface speaks for itself, requiring little to no additional training, which is a major plus. Advanced threat protection features in Zscaler Cloud Firewall are practically the key component that every customer wants. Unfortunately, it is an option and not included in the basic package. Clients need to pay for the next higher bundle to access it, but practically all clients I have dealt with want this feature 100%. Regarding visibility, I can confirm that Zscaler Cloud Firewall indeed includes a feature for application layer visibility embedded in the service. It provides visibility into what you're doing, which is especially interesting nowadays when discussing AI tools, as companies do not want their employees to copy-paste sensitive information into AI systems. We have seen cases such as Samsung's chip design where sensitive info got exposed. The visibility of applications, including cloud applications and AI tools, is significant for compliance with data policies, and you can also run reports and alerts on it.

Read full review

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Top Industries

By visitors reading reviews

Computer Software Company

12%

Comms Service Provider

Manufacturing Company

Financial Services Firm

Computer Software Company

23%

Manufacturing Company

Government

Outsourcing Company

Manufacturing Company

13%

Computer Software Company

11%

Financial Services Firm

Transportation Company

Company Size

By reviewers

Large Enterprise

Midsize Enterprise

Small Business

By reviewers
Company Size	Count
Small Business	357
Midsize Enterprise	133
Large Enterprise	188

By reviewers
Company Size	Count
Small Business	20
Midsize Enterprise	14
Large Enterprise	18

By reviewers
Company Size	Count
Small Business	5
Midsize Enterprise	2
Large Enterprise	12

Questions from the Community

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What are the biggest technical differences between Sophos UTM and Fortinet FortiGate?

As a solution, Sophos UTM offers a lot of functionality, it scales well, and the stability and performance are quite ...

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What do you like most about Cisco IOS Security?

Cisco IOS Security is a mature product with extensive capabilities, serving as the base for the defense layer. It off...

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What is your experience regarding pricing and costs for Cisco IOS Security?

The cost of Cisco IOS Security for customers is on the higher end of pricing compared to the competition, depending o...

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What needs improvement with Cisco IOS Security?

Regarding improvements in Cisco IOS Security, what consistently confuses me is the inability of Cisco to maintain a c...

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Which lesser known firewall product has the best chance at unseating the market leaders?

Netscope, Zscaler if they continue route they are on now. FIrewalls needs great deal of automation on each end, datac...

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What is your experience regarding pricing and costs for Zscaler Cloud Firewall?

Zscaler Cloud Firewall is quite expensive compared to competitors. However, it offered moderate value for money.

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What needs improvement with Zscaler Cloud Firewall?

In terms of improvements for Zscaler Cloud Firewall, I think every product has needed enhancements over time, and cur...

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Comparisons

Sophos Firewall vs Fortinet FortiGate

Compared 20% of the time

Cisco Secure Firewall vs Fortinet FortiGate

Compared 13% of the time

Netgate pfSense vs Fortinet FortiGate

Compared 6% of the time

OPNsense vs Fortinet FortiGate

Compared 3% of the time

Palo Alto Networks NG Firewalls vs Fortinet FortiGate

Compared 3% of the time

More Fortinet FortiGate Competitors

Cisco Secure Firewall vs Cisco IOS Security

Compared 18% of the time

Cisco Meraki MX vs Cisco IOS Security

Compared 8% of the time

OPNsense vs Cisco IOS Security

Compared 8% of the time

Cato SASE Cloud Platform vs Cisco IOS Security

Compared 8% of the time

Juniper SRX Series Firewall vs Cisco IOS Security

Compared 6% of the time

More Cisco IOS Security Competitors

Check Point Quantum Force vs Zscaler Cloud Firewall

Compared 16% of the time

Palo Alto Networks NG Firewalls vs Zscaler Cloud Firewall

Compared 10% of the time

Azure Firewall vs Zscaler Cloud Firewall

Compared 8% of the time

Huawei NGFW vs Zscaler Cloud Firewall

Compared 5% of the time

Palo Alto Networks VM-Series vs Zscaler Cloud Firewall

Compared 4% of the time

More Zscaler Cloud Firewall Competitors

Product Reports

Buyer's Guide

Fortinet FortiGate

January 2026

Download Fortinet FortiGate product report

Buyer's Guide

Cisco IOS Security

January 2026

Download Cisco IOS Security product report

Buyer's Guide

Zscaler Cloud Firewall

January 2026

Download Zscaler Cloud Firewall product report

Also Known As

Fortinet FortiGate Next-Generation Firewall

IOS Security

No data available

Overview

Fortinet FortiGate is a versatile network security tool offering features like VPN, firewall, web filtering, intrusion prevention, and scalability. It is known for its performance and integration with other Fortinet products, making it a preferred choice for robust cybersecurity.

Fortinet FortiGate stands out as a comprehensive cybersecurity solution with strong performance and ease of configuration. It delivers unified threat management, integrating features such as dynamic routing, SD-WAN support, and centralized management. Despite its strengths, improvements in the web interface's stability, pricing structures, and reporting capabilities are needed. Users seek better integration with third-party tools and automation advancements to enhance the experience further. These enhancements, alongside improvements in bandwidth management and the reduction of licensing costs, are points of interest for users looking to capitalize on FortiGate's extensive capabilities.

What are Fortinet FortiGate's key features?

VPN: Ensures secure remote connections.
Firewall: Protects against unauthorized access.
Web Filtering: Blocks malicious sites and content.
Application Control: Manages and controls applications.
Intrusion Prevention: Detects and prevents vulnerabilities.
SSL Inspection: Enhances security by inspecting encrypted traffic.

What benefits should be considered when evaluating Fortinet FortiGate?

Affordability: Offers cost-effective security solutions.
Reliability: Known for consistent and stable performance.
Integration: Seamlessly integrates with other Fortinet products.
Comprehensive Protection: Provides broad threat protection capabilities.

Fortinet FortiGate is widely implemented across industries as a primary firewall system for securing internet gateways and safeguarding data centers. It supports businesses in achieving SD-WAN integration and enhances cybersecurity by providing essential features like antivirus, web filtering, and application control. Enterprises utilize FortiGate for securing remote connections and ensuring compliance with security standards, making it adaptable for different network sizes and industries.

Fortinet

Cisco IOS Software delivers a sophisticated set of security capabilities for a comprehensive, layered security approach throughout your network infrastructure. Cisco IOS security technologies help to defend critical business processes against attack and disruption, protect privacy, and support policy and regulatory compliance controls.

Cisco

Zscaler enables the world’s leading organizations to securely transform their networks and applications for a mobile and cloud first world. Its flagship services, Zscaler Internet Access and Zscaler Private Access, create fast, secure connections between users and applications, regardless of device, location, or network. Zscaler services are 100% cloud-delivered and offer the simplicity, enhanced security, and improved user experience that traditional appliances or hybrid solutions are unable to match. Used in more than 185 countries, Zscaler operates the world’s largest cloud security platform, protecting thousands of enterprises and government agencies from cyberattacks and data loss.

Check more details: https://www.zscaler.com/produc...

Zscaler

Sample Customers

Amazon Web Services, Microsoft, IBM, Cisco, Dell, HP, Oracle, Verizon, AT&T, T-Mobile, Sprint, Vodafone, Orange, BT Group, Telstra, Deutsche Telekom, Comcast, Time Warner Cable, CenturyLink, NTT Communications, Tata Communications, SoftBank, China Mobile, Singtel, Telus, Rogers Communications, Bell Canada, Telkom Indonesia, Telkom South Africa, Telmex, Telia Company, Telkom Kenya

Arup Group, Brunel University London, City of Biel, Gobierno de Castilla-La Mancha, K&L Gates , New South Wales Rural Fire Service, Offshore Northern Seas, Transplace

Zenith Live, Azure, Carlsberg Group

Buyer's Guide

Cisco IOS Security vs. Zscaler Cloud Firewall

December 2025

Free Report: Cisco IOS Security vs. Zscaler Cloud Firewall

Find out what your peers are saying about Cisco IOS Security vs. Zscaler Cloud Firewall and other solutions. Updated: December 2025.

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