Abstract: A system backs up computer files to a remote site via modem, LAN, WAN, or other network device 16. Files of a user computer that are found in a common library at the remote site initially are not copied to the remote site, whereas files not in the library are copied to the remote site and potentially automatically added to the library when a sufficient number of computers contain the files. Then, periodically or continuously if the user is online via the modem, the user computer determines which blocks have been changed, and the user computer transmits only changed blocks to the remote site. The blocks are gathered in "chunk" files, and when a chunk file reaches a predetermined size, it is transmitted to the remote site for updating the back up version of the respective file. The process then resumes identifying changed blocks.

Abstract: A portable computer back up system copies user-selected files for back up as the computer is being used, and when the computer senses a network connection and the network is relatively available, the blocks of the files to be backed up are interleaved with, e.g., metadata and transmitted to a remote facility via the network. The back up system suspends the backing up of files if a disk space limit is reached, transmits any copied files when the network is available, deleting the back up copies of the files from disk, and then resumes copying files for back up. Also, each time the portable computer is connected to a network, it determines what other devices are on the network, and if the computer recognizes the network configuration, the computer reconfigures its settings as appropriate for, e.g., printing to the printer that happens to be connected to the particular network to which the portable computer is connected at the time.

Abstract: A system backs up computer files to a remote site via modem. Files of a user computer that are found in a common library at the remote site initially are not copied to the remote site, whereas files not in the library are copied to the remote site. Then, periodically the user computer determines which blocks have been changed, and the user computer transmits only changed blocks to the remote site. The blocks are gathered in "chunk" files, and when a chunk file reaches a predetermined size, it is transmitted to the remote site for updating the back up version of the respective file. The process then resumes identifying changed blocks. In addition to flagging the changed block for transfer, the process resynchronizes the local data file with the backed up version using a two-step comparison, first comparing the first two characters in the block with a pre-stored character set, and then, if the first comparison results in a match, comparing a digital signature of the changed block with a pre-stored signature.

Abstract: A system backs up computer files to a remote site via modem. Files of a user computer that are found in a common library at the remote site initially are not copied to the remote site, whereas files not in the library are copied to the remote site. Then, periodically the user computer determines which blocks have been changed, and the user computer transmits only changed blocks to the remote site. The blocks are gathered in "chunk" files, and when a chunk file reaches a predetermined size, it is transmitted to the remote site for updating the back up version of the respective file. The process then resumes identifying changed blocks. In addition to flagging the changed block for transfer, the process resynchronizes the local data file with the backed up version using a two-step comparison, first comparing the first two characters in the block with a pre-stored character set, and then, if the first comparison results in a match, comparing a digital signature of the changed block with a pre-stored signature.