SONiC has Ethernet naming based on the lanes like Ethernet0, Ethernet4, Ethernet8… Ethernet252, This is not very user-friendly and the CLI Ethernet names are not mapped to the Physical front panel ports.
To avoid this and provide a better user experience, Interface Mapping Feature is implemented by exposing the Front Panel ports directly to the user and all the mapping to SONiC and ASIC is handled by OPBNOS internally.