Each VC is associated to an interface, or virtual interface, in the ifTable as part of the service configuration, and this object defines whether the maintenance protocol will send that interface's name as it appears in the ifTable; if false, the optional element is not sent. Enabling this makes the router include the actual interface name inside the pseudowire signaling exchange, purely as a human-readable diagnostic aid for whoever is troubleshooting the far-end PE, since it has no effect on forwarding behavior at all. For example, enabling this on a pseudowire lets an admin troubleshooting from the remote PE see a name like GigabitEthernet0/1 directly in signaling diagnostics instead of only seeing opaque VC and label numbers.