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When a Mobiliti Network/Unplugged (N/U) client synchronizes with Mobiliti's synchronization server, the client transmits the delta changes to the server. After comparing the delta changes with the files read from the file server, the synchronization server sends the proposed changes back to the client in one block for confirmation. Following confirmation, the server makes the changes to the files and writes them back to the file server. This increases the speed of analysis over dial-up connections and reduces the amount of data transferred through the network. Note that the synchronization server needs to read and write entire files with the file server. So a fast LAN connection between the two is required.

N/U's iDESP (Intelligent Delta Selection Process) technology transmits only the changes made to files and not the whole file. It includes three methods of synchronizing files: byte-level differencing, write-monitor differencing and block-level differencing. Byte-level differencing compares local files with network files and calculates the differences or changes down to the byte level. Then only the changes are transmitted across the network during synchronization and backup, thus increasing the speed of synchronization. This method is capable of detecting small differences among text files, documents and spreadsheets. To reduce the time further, N/U clients can be configured to store a copy of the original file on the local drive as a reference file to compute the changes made to the original file. Note that you can limit the disk space used for reference files.

Synchronization using write-monitor differencing tracks and logs changes made to files by the applications modifying the files. At synchronization, the logged "writes" are condensed by removing duplicates, then compressed and transferred across the network. N/U uses this method to synchronize database files and Microsoft Outlook personal folder files (*.pst). If byte-level or write-modification differencing is not specified, N/U uses block-level differencing to break files down into blocks on the client side and the server side. It then compares the blocks on both sides and generates the differences down to the block level. Only the differences are transferred during synchronization and backup. Block-level differencing is applicable to all file types.