The backup technology making headlines today is "FastBIT^tm binary patching". Originally developed over 8 years ago as a method for upgrading software, binary patching has received widespread acceptance by many of the world's largest hardware and software manufacturers including IBM, Compaq and Microsoft.

To cut costs and decrease the time to market, manufacturers distribute their updates as tiny files or "patches" containing only the binary difference between the old and new version of their software. Once received by the client, these patches are applied or merged into the existing file instantly upgrading it to the latest release. An obvious advantage is that the size of the upgrade is reduced significantly. This permits clients to use modem dial-up connections to obtain software updates instead of the more traditional forms of distribution such as floppy disk or CD-ROM.

Although FastBIT binary patching may sound similar to block technology, it differs in one significant aspect: FastBIT binary patching does not evaluate a file as a collection of discrete blocks rather, as a continuous string of binary data.

Utilizing a complex algorithm and special memory management, FastBIT binary patching is capable of comparing files and extracting "patches" of binary data that represent only the specific changes to those files. Simply put, If only 1 kilobyte of data has actually changed in the file, then only a 1-kilobyte patch is extracted for backup thus eliminating the overhead imposed by block technology methodology.

In a real world backup scenario, each discrete patch is combined with those from other files into a single archive and then compressed. This compressed archive is transferred to a backup server, and the patches are extracted and saved either discretely or are applied to the server's copy of the original data file.

Observing the binary patching process, one can quickly see a significant decrease in backup size over that of the block technology system. This is clearly demonstrated in table 1, which outlines the results of a carefully designed and executed test.