<title>Back end examples</title> <body bgcolor=ffffff> <h2>Back end examples</h2> <p> Here are some examples of the "back ends" that could be used by various types of project. <p> <b>SETI@home with local data servers</b> <ul> <li> A <b>splitter program</b> generates data files. For each data file, calls the BOINC server library to create a workunit record and several result records, and stores the data file on disk of a data server. <li> A <b>garbage collector</b> program deletes data files for which enough results have been returned. Generates new result records as needed. <li> A <b>result handler</b> program checks for new results. Parses result files, and transfers contents to a separate "science database". Does redundancy checking, and marks result records as valid or invalid. </ul> <p> <b>SETI@home with remote data servers</b> <p> As above, but the splitter program writes data files to DLT tape. The result records are generated, using the URL of a selected data server. The tape is mailed to the data server. An operator at the data server transfers the files to disk, than uses a web control panel to mark the batch as ready, which marks the result records as ready.