Managed network security services combine day-to-day network operations with controls that protect users, devices, applications, and data across on-premises, cloud, and hybrid environments. As organizations adopt distributed work, multi-cloud infrastructure, and internet-first connectivity, security increasingly has to be built into the network rather than managed as a separate layer. Common priorities include firewall administration, SASE, zero trust access, continuous monitoring, threat detection, incident response, and policy management. The right service model depends on network complexity, regulatory requirements, internal security capacity, and how much operational responsibility a provider is expected to assume.
1. Itexus
Itexus combines software engineering, DevOps, cloud infrastructure, and cybersecurity work for organizations that need security integrated into production systems. Its cybersecurity capabilities include security audits, penetration testing, threat detection, compliance readiness, access controls, infrastructure hardening, and incident response. The company also works with network segmentation, firewalls, endpoint protection, encrypted communications, and continuous monitoring as part of its broader infrastructure and application security work.
This model is particularly relevant for businesses that want network security decisions coordinated with application architecture and cloud operations. Instead of treating infrastructure controls as a separate project, Itexus can connect security reviews, deployment practices, access management, monitoring, and post-launch support within the same engineering engagement.
Key Facts
- Best for: Product companies that want network security integrated with software and cloud engineering
- Core services: Managed network security, security audits, penetration testing, threat detection, infrastructure controls, DevOps, cloud operations
- Specialization: Secure application and infrastructure engineering
- Headquarters: Dover, DE, USA
- Founded: 2013
- Team size: 150+ engineers
Contact Information
- Website: itexus.com
- Email: moc.suxeti@ofni
- Address: 8, The Green, STE road, Dover, DE 19901, United States
- LinkedIn: www.linkedin.com/company/itexus
- Facebook: www.facebook.com/itexus
- Twitter: x.com/ItexusSoft
- Instagram: www.instagram.com/itexus.
2. LevelBlue
LevelBlue runs managed network security as a service line of its own. LevelBlue handles configuration, monitoring and updates, and its published services include Managed DDoS Defense with round-the-clock monitoring and mitigation, managed next-generation firewalls with unified visibility, and a content delivery network with cloud-based protection. These cover on-premises, cloud and hybrid environments, with 24/7 incident response support.
The same portfolio offers managed SASE, managed SSE, email and data security, and managed detection and response. LevelBlue's published case studies include a healthcare provider, a state and local government, and school districts, mainly on DDoS protection and uptime. It suits organizations that want firewall, DDoS and SASE operations under one provider.
Key Facts
- Best for: Organizations outsourcing firewall, DDoS and SASE operations
- Core services: Managed DDoS defense, next-gen firewall, managed SASE, SSE, MDR
- Specialization: Managed network security across on-premises, cloud and hybrid environments
- Headquarters: Dallas, TX, USA
- Founded: 2024
- Team size: 501–1,000 employees
Contact Information
- Website: levelblue.com
- Address: 6010 West Spring Creek Pkwy, Plano, TX 75024, USA
- LinkedIn: www.linkedin.com/company/levelbluecyber
3. Lumen
Lumen combines its network services with managed security built on threat intelligence from its Black Lotus Labs team. For network protection it offers DDoS Mitigation Service, DDoS Essentials for common volumetric attacks, Lumen Defender for blocking malicious IP traffic, Adaptive Network Security for cloud-based firewalling, and Managed Premises Firewall Services on Cisco, Fortinet and Palo Alto Networks hardware.
Lumen also sells managed SASE with Fortinet or Versa, managed zero trust network access with Zscaler, and fully managed or co-managed SD-WAN. For monitoring it adds a virtual SOC, managed SIEM and Lumen Defender AMDR for 24/7 detection and response. It fits enterprises that want connectivity and network security from one provider.
Key Facts
- Best for: Enterprises buying connectivity and network security together
- Core services: DDoS mitigation, managed firewalls, managed SASE, ZTNA, SD-WAN, vSOC
- Specialization: Carrier-backed network security with Black Lotus Labs threat intelligence
- Headquarters: Monroe, LA, USA
- Team size: 10,001+ employees
Contact Information
- Website: lumen.com
- LinkedIn: www.linkedin.com/company/lumentechnologies
4. NTT DATA
NTT DATA provides managed network and cybersecurity services for large, distributed environments. Its managed security portfolio covers the security lifecycle, while its managed network services combine network operations with managed security functions. Published service material includes firewall management, threat visibility, secure connectivity, and ongoing monitoring, giving enterprises a way to place network performance and security operations under coordinated management.
The company is a practical fit for organizations with complex global infrastructure, multiple sites, hybrid cloud environments, or established security teams that need additional operational capacity. Its scale also supports programs where network transformation, observability, and security policy need to remain aligned across regions.
Key Facts
- Best for: Large enterprises with complex multi-site or global networks
- Core services: Managed networking, managed security, firewall management, monitoring, secure connectivity
- Specialization: Enterprise-scale network and security operations
- Headquarters: Tokyo, Japan
- Founded: 1988
- Team size: 10,001+ employees
Contact Information
- Website: www.nttdata.com
- Phone: +44 (0) 20 3933 5500
- Address: Epworth House, 25 City Road, London, EC1Y 1AA, United Kingdom
- LinkedIn: www.linkedin.com/company/ntt-data
- Twitter: x.com/nttdata
- Instagram: www.instagram.com/nttdata
5. A-listware
A-listware delivers managed IT services that include networking and managed security. Its infrastructure scope covers switches, routers, Wi-Fi, modems, and network servers, while its security work includes firewalls, security monitoring, identity and access controls, vulnerability assessments, security audits, penetration testing, and security program planning. NOC management and 24/7 support extend that work into ongoing operations rather than one-time consulting.
This combination suits businesses that want day-to-day IT management and network protection handled within the same service relationship. The company can support organizations that need infrastructure administration, monitoring, access control, and security review without splitting those responsibilities across several providers.
Key Facts
- Best for: Businesses combining managed IT operations with network security
- Core services: Managed security, network management, firewalls, monitoring, access management, security audits
- Specialization: Integrated managed IT and security support
- Headquarters: London, UK
Contact Information
- Website: a-listware.com
- Phone: +1 (888) 337 93 73
- Email: moc.erawtsil-a@ofni
- Address: North Bergen, NJ 07047, USA
- LinkedIn: www.linkedin.com/company/a-listware
- Facebook: www.facebook.com/alistware
6. Verizon
Verizon combines managed network services with a broad portfolio of enterprise security capabilities. Its services cover managed SD-WAN, LAN, cloud and network security, DDoS protection, and SASE management, backed by continuous operations and monitoring. That makes it relevant for organizations looking to secure connectivity across branches, remote users, cloud applications, and internet-facing services.
The service model is well suited to enterprises that prefer one provider for connectivity, network operations, and security controls. Verizon's network footprint also makes it useful for programs where secure access and WAN modernization have to be coordinated across many locations rather than deployed as isolated security products.
Key Facts
- Best for: Distributed enterprises combining connectivity and security management
- Core services: Managed SD-WAN, SASE, network security, DDoS protection, managed LAN
- Specialization: Secure enterprise connectivity and managed network operations
Contact Information
- Website: www.verizon.com
- Phone: +18338982779
- Address: 275 Greenwich St, New York, NY, 10007
- LinkedIn: www.linkedin.com/company/verizonbusiness
- Facebook: www.facebook.com/verizonbusiness
- Twitter: x.com/verizonbusiness
- Instagram: www.instagram.com/verizonbusiness
7. IBM
IBM offers Managed Network Security Services focused on the operation and monitoring of network security devices and policies. The service includes device and policy management, security monitoring, and alerting across technologies such as next-generation firewalls, intrusion detection and prevention systems, unified threat management platforms, and secure web gateways. IBM also connects network controls with broader security and resiliency services for hybrid environments.
This approach fits enterprises that already operate heterogeneous security technologies and need consistent management across them. It is especially relevant where network security operations must integrate with established governance, cloud security, incident processes, and wider cybersecurity programs.
Key Facts
- Best for: Enterprises with heterogeneous network security environments
- Core services: Security device management, policy management, monitoring, alerting, firewall and IDS/IPS support
- Specialization: Managed security operations for complex hybrid infrastructure
- Headquarters: Armonk, NY, USA
- Founded: 1911
- Team size: 10,001+ employees
Contact Information
- Website: www.ibm.com
- Phone: 1-800-426-4968
- Address: 1 New Orchard Road Armonk, New York, 10504-1722, United States
- LinkedIn: www.linkedin.com/company/ibm
- Twitter: x.com/ibm
- Instagram: www.instagram.com/ibm
8. Kyndryl
Kyndryl provides managed network services with security built into WAN, SASE, and network modernization programs. Its managed SASE services bring together secure web gateway, zero trust network access, cloud access security broker, firewall-as-a-service, and SD-WAN, with support from network and security operations centers. Kyndryl also uses continuous monitoring, automated governance, and integrated NOC and SOC operations for enterprise networks.
The company is a strong fit for large organizations modernizing legacy networks while moving toward cloud-delivered security. Its service model can cover consulting, design, implementation, and managed operations, which is useful when network transformation and security policy need to move together.
Key Facts
- Best for: Large enterprises modernizing WAN and security architecture
- Core services: Managed network services, SASE, ZTNA, FWaaS, SD-WAN, network monitoring
- Specialization: Integrated NOC, SOC, and secure network transformation
- Headquarters: New York, NY, USA
- Founded: 2021
- Team size: 10,001+ employees
Contact Information
- Website: www.kyndryl.com
- Phone: +1.855.596.3795
- Email: moc.lyrdnyk@selas
- Address: 2nd Floor, 100 Liverpool Street, London, United Kingdom, EC2M 2AT
- LinkedIn: www.linkedin.com/company/kyndryl
- Twitter: x.com/kyndryl
9. OSKI Solutions
OSKI Solutions provides cybersecurity and infrastructure engineering services that cover application security, penetration testing, security audits, DevSecOps, identity and access management, and cloud and infrastructure hardening. Its broader managed IT capabilities make those controls relevant to organizations that need ongoing technical operations rather than an isolated security assessment.
The company is a good match for businesses that want network and infrastructure protection tied to development and cloud practices. Security reviews, access controls, hardening, and operational support can be coordinated around the same systems, which is useful for teams with compact internal IT departments or cloud-heavy environments.
Key Facts
- Best for: Businesses combining managed IT, cloud engineering, and security work
- Core services: Security audits, penetration testing, IAM, DevSecOps, infrastructure hardening
- Specialization: Engineering-led security and managed infrastructure
- Headquarters: Tallinn, Estonia
- Team size: 51–200 employees
Contact Information
- Website: oski.site
- Email: etis.ikso@tcatnoc
- Address: Kaupmehe tn 7-120, Tallinn, 10114, Estonia
- LinkedIn: www.linkedin.com/company/oski-solutions
10. Orange Business
Orange Business combines managed connectivity with cybersecurity capabilities delivered through Orange Cyberdefense. Its portfolio supports SASE, zero trust, threat management, secure access, and managed security services alongside enterprise networking. This makes it relevant for organizations that want security controls designed around how users, branches, cloud services, and applications actually connect.
The provider is especially suited to multinational businesses that need consistent network and security operations across many countries. Its ability to integrate connectivity and security can reduce the operational divide between network teams and security teams when enterprises are moving toward cloud-first access models.
Key Facts
- Best for: Multinational enterprises with integrated connectivity and security needs
- Core services: SASE, zero trust, threat management, managed security, enterprise networking
- Specialization: Global secure connectivity and cybersecurity integration
- Headquarters: Paris, France
- Founded: 2006
- Team size: 10,001+ employees
Contact Information
- Website: www.orange-business.com
- LinkedIn: www.linkedin.com/company/orange-business-services
- Facebook: www.facebook.com/orangebusiness
- Twitter: x.com/orangebusiness
11. Tata Communications
Tata Communications provides managed network and security services for global enterprises, including WAN, SD-WAN, Wi-Fi and LAN, secure connectivity, and 24/7 managed security monitoring. Its portfolio is designed for organizations that need network transformation and security controls to operate together across branches, cloud environments, and remote access patterns.
The company is particularly relevant to businesses with international operations and complex connectivity requirements. By combining network management with security services, it can support programs where performance, availability, visibility, and protection need a common operating model rather than separate vendors for each layer.
Key Facts
- Best for: Global enterprises with complex connectivity requirements
- Core services: WAN, SD-WAN, managed security, network monitoring, LAN and Wi-Fi
- Specialization: Global managed connectivity with integrated security
- Headquarters: Mumbai, India
- Founded: 1986
- Team size: 10,001+ employees
Contact Information
- Website: www.tatacommunications.com
- Phone: +1 (703) 547-5900
- Address: 11911 Freedom Drive, Suite 250, Reston, VA, 20190 USA
- LinkedIn: www.linkedin.com/company/tata-communication
- Twitter: x.com/tata_comm
- Instagram: www.instagram.com/tata_comm
12. Fortinet
Fortinet delivers managed network security through services built around the Fortinet Security Fabric and FortiGate platform. Managed FortiGate Service provides 24/7 deployment, configuration, change management, incident response, system hardening, and centralized management. Coverage extends across next-generation firewalls, SD-WAN, LAN edge, zero trust network access, and related security policies.
Fortinet also supports managed SASE and managed secure networking models for service providers and enterprise customers. The company is a practical choice for organizations standardizing on Fortinet technology and looking for direct operational support around firewall policy, secure connectivity, and network security lifecycle management.
Key Facts
- Best for: Organizations standardizing on Fortinet network security
- Core services: Managed FortiGate, NGFW management, SD-WAN, ZTNA, SASE, incident response
- Specialization: Fortinet-based managed secure networking
- Headquarters: Sunnyvale, CA, USA
- Founded: 2000
- Team size: 10,001+ employees
Contact Information
- Website: www.fortinet.com
- Phone: +1-866-868-3678
- Email: moc.laredeftenitrof@ofni
- Address: 909 Kifer Road, Sunnyvale, CA 94086, USA
- LinkedIn: www.linkedin.com/company/fortinet
- Facebook: www.facebook.com/fortinet
- Twitter: x.com/Fortinet
- Instagram: www.instagram.com/fortinet
13. MCK
MCK provides managed network and security services for businesses in the United States and Canada. Its managed network portfolio includes LAN, switches, Wi-Fi, secure gateways, SD-WAN, zero trust network access, data loss prevention, and SASE. The company also operates managed SOC services with 24/7 monitoring, analysis, and incident response.
This combination is useful for small and midsize organizations that want one provider to manage both connectivity and defensive controls. MCK's SASE offering brings SD-WAN, firewall-as-a-service, secure web gateway, CASB, and zero trust access into a cloud-managed model, while its SOC services add continuous security oversight.
Key Facts
- Best for: Small and midsize organizations in the United States and Canada
- Core services: Managed LAN, SD-WAN, SASE, ZTNA, DLP, managed SOC
- Specialization: Unified managed network and security operations
Contact Information
- Website: www.mck.com
- Phone: (716) 817-8625
- Address: 221 Commerce Dr., Amherst, NY, 14228
14. Gilzor
Gilzor supports software products from architecture and development through production operations, with security incorporated into deployment, monitoring, permissions, data protection, and infrastructure reviews. Its production-readiness work can cover authentication, access controls, cloud configuration, reliability, and operational security risks, while ongoing support extends those controls beyond launch.
The company fits technology businesses whose network security needs are closely connected to application and cloud operations. Its approach is less about operating a carrier-scale network and more about making sure production infrastructure, access paths, deployment practices, and monitoring are treated as part of the same engineering system.
Key Facts
- Best for: Product teams that want security integrated with production engineering
- Core services: Production readiness, cloud operations, monitoring, infrastructure security, access reviews
- Specialization: Application and infrastructure security within software engineering
- Headquarters: Warsaw, Poland
Contact Information
- Website: www.gilzor.com
- Email: moc.rozlig@stcatnoc
- Address: Poland, Warsaw, Office 58, street Adama Mickiewicza 37, 01-625
- LinkedIn: www.linkedin.com/company/gilzor-softwaredevelopment
Comparison Table
| Company | Best for | Headquarters | Founded | Team size |
| Itexus | Product companies that want network security integrated with software and cloud engineering | Dover, DE, USA | 2013 | 150+ engineers |
| LevelBlue | Organizations outsourcing firewall, DDoS and SASE operations | Dallas, TX, USA | 2024 | 501–1,000 employees |
| Lumen | Enterprises buying connectivity and network security together | Monroe, LA, USA | — | 10,001+ employees |
| NTT DATA | Large enterprises with complex multi-site or global networks | Tokyo, Japan | 1988 | 10,001+ employees |
| A-listware | Businesses combining managed IT operations with network security | London, UK | — | — |
| Verizon | Distributed enterprises combining connectivity and security management | — | — | — |
| IBM | Enterprises with heterogeneous network security environments | Armonk, NY, USA | 1911 | 10,001+ employees |
| Kyndryl | Large enterprises modernizing WAN and security architecture | New York, NY, USA | 2021 | 10,001+ employees |
| OSKI Solutions | Businesses combining managed IT, cloud engineering, and security work | Tallinn, Estonia | — | 51–200 employees |
| Orange Business | Multinational enterprises with integrated connectivity and security needs | Paris, France | 2006 | 10,001+ employees |
| Tata Communications | Global enterprises with complex connectivity requirements | Mumbai, India | 1986 | 10,001+ employees |
| Fortinet | Organizations standardizing on Fortinet network security | Sunnyvale, CA, USA | 2000 | 10,001+ employees |
| MCK | Small and midsize organizations in the United States and Canada | — | — | — |
| Gilzor | Product teams that want security integrated with production engineering | Warsaw, Poland | — | — |
How to Choose a Managed Network Security Provider
A managed network security provider will control the firewalls, access policies and connectivity your whole business runs on. The decision is about whether they can operate your specific architecture, keep policies clean as it changes, and detect and respond to threats without causing outages. Weigh operational discipline as heavily as the technology they sell.
Platform depth and certifications. Ask which firewall, SD-WAN and SASE platforms the provider manages at scale and how many certified engineers they have for each. Providers often favour one or two vendors. If they push a full replacement of your current platform, ask for the business case. Deep experience with your existing stack can deliver value faster than a costly migration.
Change and policy management. Review how firewall rule requests are submitted, approved, tested and documented, and the turnaround time for standard and emergency changes. Ask whether they run periodic rule reviews to remove unused or overly permissive rules. Rule sprawl is one of the most common network security weaknesses, and a provider that only adds rules makes it worse over time.
Zero trust and remote access. If you are moving from VPNs to zero trust network access, ask how the provider designs access policies around identity and device posture, integrates with your identity provider, and phases the rollout. Request examples of migrations for organisations of similar size. Generic claims about zero trust mean little without a concrete plan for which applications move first.
Monitoring and threat response. Clarify whether the service includes 24/7 security monitoring of network traffic and firewall logs, or only device health monitoring. Ask what happens when malicious traffic is detected: who investigates, who blocks, and within what timeframe. Confirm how network alerts are shared with your SOC or MDR provider so incidents are not handled in two disconnected places.
Availability and configuration backup. Network security changes can take a business offline. Ask about high-availability designs, configuration backups, rollback procedures and maintenance windows. Request the uptime commitment for managed devices and cloud security services, with service credits. A provider should be able to restore a failed firewall's configuration quickly and explain how firmware updates are tested before deployment.
Visibility and reporting. Ask for a sample monthly report and access to a client portal. Useful reporting covers blocked threats, policy changes, vulnerability and firmware status, and capacity trends, with enough detail for audits under PCI DSS, ISO 27001 or similar frameworks. Make sure you keep read access to your own devices and logs rather than depending entirely on the provider for visibility.
Conclusion
Managed network security is moving toward convergence: network operations, identity, cloud access, firewall policy, and threat monitoring increasingly sit inside the same operating model. Strong providers combine technical controls with continuous management, clear escalation paths, and enough visibility to keep policies consistent as environments change. SASE and zero trust are important architectural directions, but they work best when paired with disciplined configuration, monitoring, and incident processes. Buyers should pay close attention to where responsibility starts and ends, which technologies the provider will operate directly, how changes are governed, and what level of 24/7 response is included. The most sustainable service relationships are built around measurable operational responsibilities rather than a long catalog of security products.
Frequently Asked Questions
What do managed network security services include?
Managed network security usually includes firewall management, intrusion prevention, secure web gateway or SASE administration, VPN or zero trust access, and monitoring of network devices and traffic. Many providers add vulnerability scanning, DDoS protection and SD-WAN management. Service levels vary widely, so check whether monitoring covers security events around the clock or only device availability.
How much do managed network security services cost?
Pricing is typically a monthly fee per managed device, per site or per user for cloud-delivered services, sometimes bundled with hardware and licences. Costs depend on the number of locations and firewalls, the platforms used, monitoring hours, change volumes and compliance reporting. Hardware refreshes and major migrations, such as moving to SASE, are usually quoted as separate projects.
What is the difference between SASE and a managed firewall?
A managed firewall protects traffic at a specific site or data centre, while SASE delivers network security and connectivity from the cloud to users wherever they are. SASE combines functions such as secure web gateway, cloud access security, zero trust access and SD-WAN. Many organisations run both during a transition, keeping firewalls for data centres and branches while moving remote users to SASE.
How long does it take to onboard a managed network security provider?
Onboarding usually takes several weeks, depending on the number of sites and devices and the quality of existing documentation. The provider reviews configurations and rule sets, deploys monitoring, sets up change processes and agrees escalation contacts. If a platform migration or SASE rollout is part of the scope, it is typically phased over several months to limit disruption.
Can we keep our internal network team with a managed service?
Yes, many organisations use a co-managed model in which the internal team keeps architecture decisions and owns certain systems while the provider handles monitoring, routine changes and after-hours coverage. Define clearly who can make changes, how they are approved, and who responds to incidents at each time of day. Shared access without clear rules leads to conflicting changes and gaps in accountability.