Fortinet FortiGate FG-91G: Converged NGFW with SD-WAN for Modern Enterprise Branches

The Fortinet FortiGate FG-91G is engineered for security-driven networks at distributed enterprise sites, delivering a powerful convergence of Next-Generation Firewall (NGFW) capabilities and SD-WAN in a compact, versatile appliance. Built to protect branch offices, retail locations, manufacturing floors, and remote sites, the FG-91G blends advanced threat protection with intelligent networking to simplify deployment, reduce costs, and accelerate secure digital transformation. With FortiGuard AI/ML-based security services, real-time threat intelligence, and seamless integration into the Fortinet Security Fabric, this appliance provides comprehensive protection and centralized management across your entire network. The FG-91G is designed to be easy to deploy, scalable to evolving needs, and capable of enforcing consistent security policies whether your users connect locally, remotely, or through cloud services. This combination of firewall power and SD-WAN agility makes it an ideal choice for organizations seeking a resilient, security-first WAN architecture that can adapt to changing workloads and growing bandwidth requirements without compromising protection.

• The FG-91G delivers a converged Next-Generation Firewall (NGFW) and SD-WAN solution, unifying threat prevention with intelligent path selection to simplify branch networking while maintaining robust security. With security-first networking, you gain application-aware routing, automated failover, and optimized traffic flows that keep critical applications responsive even during WAN disruptions.
• FortiGuard AI/ML security services power proactive threat prevention across the network. The FG-91G leverages AI-driven threat detection, real-time updates, and multi-layer protection—including intrusion prevention, application control, TLS/SSL inspection, and antivirus capabilities—to block emerging attacks before they impact users and endpoints.
• Security Fabric integration ensures visibility and coordinated responses across Fortinet devices. Policies, logs, and threat intelligence are shared across your security stack, enabling automated threat containment, rapid incident response, and unified reporting from on-premises FortiGate devices to cloud-based management consoles.
• Administrators benefit from streamlined deployment and management. The FG-91G runs FortiOS with intuitive dashboards, centralized policy management, and compatibility with FortiCloud, FortiManager, and FortiAnalyzer for scalable governance, audit trails, and analytics—making it easier to maintain consistent security across multiple sites.
• Flexible connectivity and resilient networking capabilities support secure remote access and site-to-site connectivity. With SD-WAN features and robust VPN options, you can ensure reliable connectivity to SaaS applications, data centers, and cloud services, while maintaining strong, policy-driven security for every branch.

Techncial Details of Fortinet FortiGate FG-91G

• Model: FG-91G
• Type: Converged NGFW with SD-WAN
• Form factor: Compact appliance suitable for branch offices and small data segments
• Security features: NGFW with IPS, application control, SSL inspection, antivirus, and anti-bot protections
• AI/ML security services: FortiGuard AI/ML threat detection and automatic security updates
• Networking: SD-WAN with dynamic path selection and policy-driven routing
• VPN: IPsec VPN and SSL VPN support for site-to-site and remote access connectivity
• Management: FortiOS, FortiCloud integration, FortiManager compatibility for centralized administration
• Fabric integration: Fortinet Security Fabric for cross-device visibility and automated responses
• Deployment focus: Security-first WAN for distributed enterprise sites and remote offices

How to install Fortinet FortiGate FG-91G

Installing the FG-91G is designed to be straightforward, enabling security professionals and IT teams to deploy quickly while preserving flexibility for evolving networks. Start by planning the topology to balance security requirements with network performance, mapping out where the FG-91G will sit in the branch or remote office, the WAN uplinks, and the internal segments it will protect. Prepare a policy framework that aligns with your organization’s access control, application usage, and compliance goals. When you’re ready to install, follow these practical steps to bring the FG-91G online and securely integrated with your broader Fortinet environment:

• Unbox and mount the FG-91G in a secure location such as a network rack or cabinet. Ensure proper ventilation and access to power and network ports. If you’re deploying at multiple sites, plan a consistent baseline configuration to simplify future management and policy replication.
• Connect the appliance to your network. Attach the WAN uplinks for SD-WAN, connect the internal LAN to the appropriate segment, and verify that management access is available from trusted consoles or workstations.
• Access the FortiGate management interface. Use a PC on the local network to navigate to the device’s default management address, log in with the initial credentials, and immediately set a strong admin password to secure the system.
• Run the initial configuration and update FortiOS. Complete the setup wizard to configure interfaces, enable the FortiGuard subscription, and apply the latest firmware and security signatures to ensure you benefit from current protections and features.
• Establish security policies and basic safeguards. Create firewall rules that enforce the principle of least privilege, enable IPS/IDS, activate application control, and configure SSL inspection as appropriate for your environment. Begin with a baseline set of policies and adjust as you monitor traffic and threat activity.
• Configure SD-WAN and VPN capabilities. Define your SD-WAN rules, enable health checks for WAN links, and create VPN connections for site-to-site or remote access as needed. Fine-tune path policies to optimize reliability and performance for critical applications.
• Monitor and refine. Use FortiAnalyzer and FortiManager to review logs, analyze traffic patterns, and fine-tune security profiles. Regularly update firmware and FortiGuard services to maintain protection against new threats and to benefit from product enhancements.

Frequently asked questions

• Q: What is the Fortinet FortiGate FG-91G best used for? A: It is a converged NGFW with SD-WAN designed to secure distributed enterprise sites, branch offices, and remote locations while simplifying WAN management and improving application performance.
• Q: Does the FG-91G support FortiGuard security services? A: Yes. It leverages FortiGuard AI/ML-based threat intelligence, intrusion prevention, application control, SSL inspection, and related services to block threats and adapt to evolving attack surfaces.
• Q: Can FG-91G integrate with Fortinet Security Fabric? A: Absolutely. The FG-91G is built to work within the Fortinet Security Fabric, enabling centralized visibility, policy synchronization, and automated threat responses across Fortinet devices.
• Q: How is the FG-91G managed? A: The device supports FortiGate OS management through the native GUI, plus cloud and enterprise-grade management with FortiCloud, FortiManager, and FortiAnalyzer for scalable governance and analytics.
• Q: What kind of connectivity does FG-91G offer? A: It provides flexible networking options suitable for SD-WAN deployment, including multiple WAN interfaces and secure VPN capabilities for site-to-site and remote access connectivity.