Software switch

A software switch is a virtual switch that is implemented at the software or firmware level and not at the hardware level. A software switch can be used to simplify communication between devices connected to different FortiGate interfaces. For example, using a software switch, you can place the FortiGate interface connected to an internal network on the same subnet as your wireless interfaces. Then devices on the internal network can communicate with devices on the wireless network without any additional configuration on the FortiGate unit, such as additional security policies.

A software switch can also be useful if you require more hardware ports for the switch on a FortiGate unit. For example, if your FortiGate unit has a 4-port switch, WAN1, WAN2, and DMZ interfaces, and you need one more port, you can create a soft switch that can include the four-port switch and the DMZ interface, all on the same subnet. These types of applications also apply to wireless interfaces, virtual wireless interfaces, and physical interfaces such as those in FortiWiFi and FortiAP units.

Similar to a hardware switch, a software switch functions like a single interface. It has one IP address and all the interfaces in the software switch are on the same subnet. Traffic between devices connected to each interface are not regulated by security policies, and traffic passing in and out of the switch are controlled by the same policy.

When setting up a software switch, consider the following:

  • Ensure that you have a back up of the configuration.
  • Ensure that you have at least one port or connection, such as the console port, to connect to the FortiGate unit. If you accidentally combine too many ports, you need a way to undo errors.
  • The ports that you include must not have any link or relation to any other aspect of the FortiGate unit, such as DHCP servers, security policies, and so on.
  • For increased security, you can create a captive portal for the switch to allow only specific user groups access to the resources connected to the switch.

Some of the difference between software and hardware switches are:

Feature

Software switch

Hardware switch

Processing

Packets are processed in software by the CPU.

Packets are processed in hardware by the hardware switch controller, or SPU where applicable.