Load protocol. Options: 1.tftp(1) -indicates that the backup is performed by using TFTP through the network port. Select tftp(1) when the transmission mode of the server is configured to TFTP.When TFTP is used in the backup, you need not enter the user name and password. 2.modem(2) -indicates that the backup is performed by using the Xmodem serial port protocol through the serial port. When you use the HyperTerminal of the OS to configure the serial port on the server, select modem(2). Loading through the serial port does not require networking and maintenance through the command line interface does not require NM software. 3.ftp(3) -indicates that the backup is performed by using FTP through the network port. Select ftp when the transmission mode of the server is configured to FTP. When FTP is used for file backup, you need to enter the user name and password. 4.sftp(5) -indicates that the backup is performed by using SFTP through the network port. Select sftp(5) when the transmission mode of the server is configured to SFTP. When SFTP is used for file backup, the instructions and data are encrypted during transmission. 5.other(6) -other. The SFTP transmission mode is recommended.