| Router configuration files that are changed frequently should be backed up. TFTP is an option that transfers configuration to a server or router after changes have been made. TFTP, however, is a non-authenticated protocol. A non-authenticated protocol requires no username or password for authentication. Anyone who can obtain access to the TFTP server can modify the configuration files. The most secure procedure is to turn TFTP on, transfer files, then turn the TFTP service off. The access list can control network traffic to the TFTP server.