Writing to this object triggers a modem file transfer action, either download to push pgModemXferSourceFilename to the modem attached at the given interface, or abort to cancel a transfer already in progress. It is the control point an admin uses to actually start or stop a firmware push to a subscriber's DSL modem after the source and destination filenames have been set. A technician who notices a transfer has stalled could write abort to this object to cancel it before retrying.