While using Internet connection speeds over 1.0 Gbps, Kerio Control might reduce the actual speed because of the advanced filtering features, such as Intrusion Prevention (IPS), Antivirus, Bandwidth Management rules and QoS, etc.
This article provides information about the maximum local bandwidth speed that was reached in the Development team's testing lab.
In the Kerio Control Interfaces -> Ports settings, 1 Gbps Full Duplex is the highest selection value available. However, the auto-negotiation option allows detecting the network card capabilities and ISP (Internet Service Provider) speed automatically.
The actual Internet speed link depends on the real speed you're getting from the ISP and your Kerio Control hardware. Depending on the system resources, such as network card, CPU, RAM, SSD, the Kerio Control can achieve up to 4.5 Gbps maximum Internet speed.
This measurement test was done in an ESXI environment and with IPS (Snort) disabled. Theoretically, Kerio Control can reach even higher values with solid hardware and ISP stability, as the necessary drivers are in place.
Note: this was NOT tested for VLANs or VPN tunnels.