Fortinet FortiGate 121G

The Fortinet FortiGate 121G is a 1RU next-generation firewall (NGFW) designed for mid-sized enterprises, branch environments and organisations that need high-performance network security with extensive connectivity options. It combines AI/ML-powered security, Secure SD-WAN and Universal ZTNA through FortiOS, helping organisations protect applications, users and devices while maintaining visibility across their network.

Powered by Fortinet's SP5 security processing architecture, the FortiGate 121G provides hardware-accelerated security and networking capabilities for demanding enterprise environments. It supports advanced threat protection, intrusion prevention, SSL inspection, application control and IPsec VPN, while providing the interfaces and throughput needed for high-traffic network deployments.

The FortiGate 121G also supports FortiLink integration, allowing FortiSwitch devices to be managed as logical extensions of the FortiGate. Combined with integration across the Fortinet Security Fabric, this provides a centralised approach to network security, access and management.

A key difference between the FortiGate 121G and the FortiGate 120G is the inclusion of a 480 GB internal SSD in the 121G. This provides onboard storage for supported local logging and storage requirements.

Key Features

The FortiGate 121G provides:

• 1RU rackmount form factor for enterprise network deployments

• Fortinet SP5 security processing architecture

• AI/ML-powered security through FortiGuard services

• Secure SD-WAN capabilities

• Universal ZTNA

• 16 × GE RJ45 ports

• 8 × GE SFP slots

• 4 × 10 GE SFP+ FortiLink ports

• Dual AC power supplies for 1+1 redundancy

• 480 GB internal SSD

• FortiLink integration with FortiSwitch

• FortiGate wireless integration with FortiAP

• FortiManager, FortiAnalyzer and Fortinet Security Fabric integration

• TPM and Bluetooth Low Energy (BLE)

Fortinet specifies the 120G series with 5.3 Gbps IPS throughput, 3.1 Gbps NGFW throughput and 2.8 Gbps threat protection throughput under its enterprise traffic mix testing.

Security and Network Performance

The FortiGate 121G is designed to combine network connectivity with security inspection at the edge. Its hardware-accelerated architecture supports security workloads while maintaining the throughput required for enterprise traffic.

Key performance figures include:

• Firewall throughput: Up to 39 Gbps for 1518-byte UDP traffic

• IPS throughput: Up to 5.3 Gbps

• NGFW throughput: Up to 3.1 Gbps

• Threat protection throughput: Up to 2.8 Gbps

• IPsec VPN throughput: Up to 35 Gbps

• SSL inspection throughput: Up to 3 Gbps

• Application control throughput: Up to 6.7 Gbps

• Concurrent TCP sessions: Up to 3 million

• New TCP sessions per second: Up to 140,000

• Firewall policies: Up to 10,000

These figures are based on Fortinet's published test conditions and should be considered alongside the specific traffic patterns, security profiles and configuration used in a deployment.

Interfaces and Hardware

The FortiGate 121G provides a dense port configuration for organisations that need multiple network connections, uplinks and FortiLink interfaces in a single rackmount appliance.

Network Interfaces

• 16 × GE RJ45 ports

• 8 × GE SFP slots

• 4 × 10 GE SFP+ FortiLink ports

• 2 × GE RJ45 management/HA ports

• 1 × RJ45 console port

• 1 × USB port

The four 10 GE SFP+ interfaces are configured as FortiLink interfaces by default and can be used to integrate FortiSwitch devices with the FortiGate. Fortinet documentation also notes that these interfaces can be reconfigured as regular network ports where required.

Storage and Power

The FortiGate 121G includes:

• 480 GB internal SSD

• Dual AC power supplies

• 1+1 power redundancy

• TPM

• Bluetooth Low Energy (BLE)

• 1RU rackmount chassis

The internal power supplies are non-hot-swappable.

Centralised Management and Fortinet Integration

The FortiGate 121G forms part of the Fortinet Security Fabric and can integrate with other Fortinet products to provide centralised security and network management.

It supports integration with:

• FortiSwitch through FortiLink

• FortiAP for managed wireless networking

• FortiManager for centralised device and policy management

• FortiAnalyzer for logging, analysis and reporting

• FortiClient for endpoint security and access control

FortiLink allows FortiSwitch devices to operate as logical extensions of the FortiGate, bringing switching and security management together within the same network architecture.

Secure SD-WAN and Universal ZTNA

The FortiGate 121G combines traditional firewall functions with technologies designed for modern distributed and hybrid networks.

Secure SD-WAN provides application-aware networking and security capabilities for organisations managing multiple WAN connections, branch offices and cloud-connected environments.

Universal ZTNA provides identity- and context-based access controls for applications and network resources. Fortinet describes Universal ZTNA as controlling and verifying access so that only validated users and devices can access protected applications.

Together, these capabilities allow the FortiGate 121G to support network security beyond the traditional perimeter firewall model.

Typical Deployment / Use Cases

The FortiGate 121G is suited to enterprise environments where organisations need a combination of high-speed network connectivity, security inspection and centralised management.

Enterprise Network Security

The FortiGate 121G can operate as a central security gateway for mid-sized enterprise networks, providing firewall, IPS, application control, VPN and threat protection capabilities from a single appliance.

Branch and Distributed Networks

The appliance can support branch and distributed network environments where organisations need consistent security policies and connectivity across multiple locations. Secure SD-WAN capabilities can also help manage application traffic across different WAN connections.

Network Segmentation

With its range of copper and fibre interfaces, the FortiGate 121G can support segmented network architectures where different departments, applications, devices or network zones require separate security policies.

Secure SD-WAN

The FortiGate 121G can be deployed at the WAN edge to combine SD-WAN networking with security inspection. This can help organisations manage connectivity between offices, data centres, cloud environments and remote locations through a unified security platform.

FortiLink Network Management

Organisations using FortiSwitch can use the FortiGate 121G as the central security and management point for their wired access layer. FortiLink integrates compatible FortiSwitch devices with the FortiGate for centralised configuration and policy management.

Local Logging and Storage

The 480 GB internal SSD distinguishes the FortiGate 121G from the diskless FortiGate 120G. The additional onboard storage can support applicable local logging and storage requirements, depending on the FortiOS configuration and deployment.

FortiGate 120G vs FortiGate 121G

The FortiGate 120G and 121G share the same core platform, interfaces and published performance specifications. The primary hardware difference is internal storage.

View data sheet: FortiGate 120G Series Data Sheet