Technical Tip: Using IANA Protocol Numbers in FortiGate Configurations

When configuring a FortiGate, it may be necessary to refer to protocols by their IANA protocol number, rather than by name. These numbers are standardized by the 'Internet Assigned Numbers Authority' (IANA) and used in the IP header 'Protocol' field.

Below are some of the most commonly used protocol numbers in FortiGate deployments:

Note:

The full list of assigned numbers is maintained by IANA and can be found here: IANA Protocol Numbers Registry

Here is an example:

Here is a protocol number used in an IPv4 Rule (Access Control List):

Here is the CLI equivalent:

config wireless-controller access-control-list
  edit "Block_ICMP"
      config layer3-ipv4-rules
        edit 1
          set dstaddr 192.168.40.42/255.255.255.255
          set protocol 1 <----- ICMP.
          set action deny
      next
   end
next
end