FortiGate 3500G
125 Gbps of IPS, 179 million concurrent sessions and two 400 GE QSFP-DD ports in 2 RU.
Full specs and SKUsFortinet · FortiGate High-End
FortiGate 3500G vs FortiGate 3800G
Of the 61 specifications Fortinet publishes across these two models, 39 differ. The differences are listed first, then what the step up actually buys and which model fits which site, then every row side by side.
The two models
FortiGate 3800G
250 Gbps of IPS, four 400 GE QSFP-DD ports and 200 million concurrent sessions - 450 million with the hyperscale licence.
Full specs and SKUsKey differences
The rows most buyers check first. All 39 differences are in the full table below.
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IPS Throughput
FortiGate 3500G125 Gbps
FortiGate 3800G250 Gbps
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NGFW Throughput
FortiGate 3500G115 Gbps
FortiGate 3800G210 Gbps
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Threat Protection Throughput
FortiGate 3500G105 Gbps
FortiGate 3800G200 Gbps
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IPv4 Firewall Throughput (1518 / 512 / 64 byte, UDP)
FortiGate 3500G595 / 590 / 420 Gbps
FortiGate 3800G795 / 793 / 453 Gbps
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IPv6 Firewall Throughput (1518 / 512 / 86 byte, UDP)
FortiGate 3500G595 / 590 / 420 Gbps
FortiGate 3800G795 / 793 / 453 Gbps
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Firewall Latency (64 byte, UDP)
FortiGate 3500G2.96 µs
FortiGate 3800G3.53 µs
Which one fits
Stepping up from the FortiGate 3500G to the FortiGate 3800G moves threat-protection throughput from 105 Gbps to 200 Gbps (1.9×), IPS throughput from 125 Gbps to 250 Gbps (2×) and NGFW throughput from 115 Gbps to 210 Gbps (1.8×). Neither choice moves TLS inspection throughput (112 Gbps against 120 Gbps) or the session setup rate (1.1 Million against 1.11 Million / 7 Million with the hyperscale licence), so a site held back by how much HTTPS can be decrypted and inspected gains nothing from the FG-3800G. The FortiGate 3500G is in fact ahead on firewall latency: 2.96 µs against 3.53 µs.
Choose the FortiGate 3500G if
- Threat-protection throughput is already enough at 105 Gbps: the FG-3800G adds 1.9× you will not use.
- The FG-3500G is ahead on firewall latency: 2.96 µs against 3.53 µs.
- The FG-3500G is ahead on power draw: 678 W / 973 W against 1496 W / 1950 W.
- Your limit is how much HTTPS can be decrypted and inspected, which the step up does not move: 112 Gbps against 120 Gbps.
Choose the FortiGate 3800G if
- Threat-protection throughput has to go past 105 Gbps: the FG-3800G publishes 200 Gbps.
- IPS throughput has to go past 125 Gbps: the FG-3800G publishes 250 Gbps.
- NGFW throughput has to go past 115 Gbps: the FG-3800G publishes 210 Gbps.
- Form Factor: Rack Mount, 3 RU, where the FG-3500G is Rack Mount, 2 RU.
22 of the 61 published rows are identical — Trusted Platform Module at Yes, Concurrent SSL-VPN Users at 30,000, Virtual Domains at 10 / 500 and Maximum Number of FortiClients at 50,000 among them — so the choice does not touch any of those.
Full specification comparison
Every published row for both models, grouped the way Fortinet groups them. A dash means the figure is not published for that model.
| Specification | FortiGate 3500G | FortiGate 3800G |
|---|---|---|
| Interfaces and Modules | ||
| Hardware Accelerated 400 GE QSFP-DD / 200 GE QSFP56 / 100 GE QSFP28 / 40 GE QSFP+ Ports | 2 | 4 |
| Hardware Accelerated 100 GE QSFP28 / 40 GE QSFP+ Slots | 4 | Not published |
| Hardware Accelerated 25 GE SFP28 / 10 GE SFP+ / GE SFP Slots | 30 | Not published |
| 10 GE / GE RJ45 Management Ports | 2 | 2 |
| USB Ports (Client / Server) | 1 | Not published |
| Hardware Accelerated 200 GE QSFP56 / 100 GE QSFP28 / 40 GE QSFP+ Slots | Not published | 6 |
| Hardware Accelerated 50 GE SFP56 / 25 GE SFP28 / 10 GE SFP+ / GE SFP Slots | Not published | 18 |
| Hardware | ||
| Console Port (RJ45) | 1 | 1 |
| Trusted Platform Module (TPM) | Yes | Yes |
| Signed Firmware Hardware Switch | Yes | Yes |
| FortiSentry | Yes | Yes |
| Included Transceivers | 2 x SFP+ (SR 10 GE) | 2 x SFP+ (SR 10 GE) |
| Onboard Storage | None | None |
| USB Ports | Not published | 1 |
| System Performance - Enterprise Traffic Mix | ||
| IPS Throughput | 125 Gbps | 250 Gbps |
| NGFW Throughput | 115 Gbps | 210 Gbps |
| Threat Protection Throughput | 105 Gbps | 200 Gbps |
| System Performance and Capacity | ||
| IPv4 Firewall Throughput (1518 / 512 / 64 byte, UDP) | 595 / 590 / 420 Gbps | 795 / 793 / 453 Gbps |
| IPv6 Firewall Throughput (1518 / 512 / 86 byte, UDP) | 595 / 590 / 420 Gbps | 795 / 793 / 453 Gbps |
| Firewall Latency (64 byte, UDP) | 2.96 µs | 3.53 µs |
| Firewall Throughput (Packet per Second) | 630 Mpps | 679.5 Mpps |
| New Sessions/Second (TCP) | 1.1 Million | 1.11 Million / 7 Million with the hyperscale licence |
| Concurrent SSL-VPN Users (Recommended Maximum, Tunnel Mode) | 30,000 | 30,000 |
| SSL Inspection Throughput (IPS, avg HTTPS) | 112 Gbps | 120 Gbps |
| SSL Inspection CPS (IPS, avg HTTPS) | 112,345 | 114,000 |
| SSL Inspection Concurrent Session (IPS, avg HTTPS) | 18 Million | 18 Million |
| Virtual Domains (Default / Maximum) | 10 / 500 | 10 / 500 |
| Maximum Number of FortiAPs (Total / Tunnel) | 4,096 / 2,048 | 8,192 / 4,096 |
| Maximum Number of FortiClients | 50,000 | 50,000 |
| System Performance | ||
| Concurrent Sessions (TCP) | 179 Million | 200 Million / 450 Million with the hyperscale licence |
| Firewall Policies | 200,000 | 400,000 |
| IPsec VPN Throughput (512 byte) | 163 Gbps | 210 Gbps |
| Gateway-to-Gateway IPsec VPN Tunnels | 40,000 | 40,000 |
| Client-to-Gateway IPsec VPN Tunnels | 200,000 | 200,000 |
| SSL-VPN Throughput | 9.8 Gbps | 27 Gbps |
| Application Control Throughput (HTTP 64K) | 197 Gbps | 315 Gbps |
| CAPWAP Throughput (HTTP 64K) | Not yet published by Fortinet | Not yet published by Fortinet |
| Maximum Number of FortiSwitches Supported | 300 | 300 |
| Maximum Number of FortiTokens | 20,000 | 20,000 |
| High Availability Configurations | Active-Active, Active-Passive, Clustering | Active-Active, Active-Passive, Clustering |
| Dimensions and Power | ||
| Height x Width x Length (mm) | 88.5 x 442.5 x 529.3 | 132.5 x 437 x 663.7 |
| Height x Width x Length (inches) | 3.5 x 17.4 x 20.8 | 5.22 x 17.2 x 26.13 |
| Form Factor (supports EIA/non-EIA standards) | Rack Mount, 2 RU | Rack Mount, 3 RU |
| AC Current (Maximum) | 12A@100V, 9A@240V | 10A@200-240VAC |
| Power Consumption (Average / Maximum) | 678 W / 973 W | 1496 W / 1950 W |
| DC Current (Maximum) | Not published | 12A@100V, 9A@240V |
| Fan Tray | Not published | Hot Swappable |
| Dimensions | ||
| Weight | 36.7 lbs (16.65 kg) | 71.65 lbs (32.5 kg) |
| Power and Environment | ||
| AC Power Supply | 100-240V AC, 60-50 Hz | 200-240V AC, 60/50 Hz |
| Heat Dissipation | 3318 BTU/h | 6654 BTU/h |
| Redundant Power Supplies | Hot Swappable, default dual AC PSU for 1+1 redundancy | Hot Swappable, 2+2 |
| Power Supply Efficiency Rating | 80+ Compliant | 80+ Platinum |
| Noise Level | 70.4 dBA | 70.4 dBA |
| Operating Temperature | 32°F to 113°F (0°C to 45°C) | 32°F to 104°F (0°C to 40°C) |
| Storage Temperature | -31°F to 158°F (-35°C to 70°C) | -31°F to 158°F (-35°C to 70°C) |
| Humidity | 5% to 90% non-condensing | 20% to 90% non-condensing |
| Forced Airflow | Front to Back | Front to Back |
| Operating Altitude | Up to 10 000 ft (3048 m) | Up to 10 000 ft (3048 m) |
| DC Power Supply | Not published | -48VDC to -60VDC, 23A |
| Compliance and Certifications | ||
| Compliance | FCC Part 15 Class A, ISED, CE, VCCI, PSE, BSMI, ANATEL, UL/cUL | Not yet published by Fortinet |
| Certifications | USGv6/IPv6 | USGv6/IPv6 |
Other comparisons in this range
Each step of the FortiGate High-End ladder, set against the model above it.
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