This read-only value names the configuration file used to persist PPPoE's permanent database records, defaulting to the built-in name '@file://PPPoEProcess.cfg' when left empty. An admin checks this to know exactly which file on the device holds the saved PPPoE configuration, useful when backing up or restoring device configuration outside of SNMP. For example, an empty usrPPPoEConfigFileName confirms the PPPoE process is using its default config file rather than a custom one.