A combination of specific protocols and ports, service usually represents a particular network application. It can be called by an application control policy to allow or deny certain network services. Service configuration is shown in the figure below.

Predefined Services: It defines the default ports of common protocols, which cannot be edited or modified. See the figure below.

Custom Services: When there is no suitable predefined service, you can manually customize services by clicking Add, as shown below.

Name: Fill in the corresponding name.

Description: Enter description information.

Protocol: Support TCP, UDP, ICMP, or other protocols. The specific port numbering can follow the corresponding protocol.

Service Groups: Combine several services into a group. To reference multiple services, you can directly reference the corresponding service group. Click Add to create a group, as shown below:

Name: Fill in the corresponding name.

Description: Enter description information.

Service: Select a service that needs to be defined.