Innovations in digital storage technology has dramatically improved the storage capacity/density of media. Higher storage capacity and density allows us to store more for cheap. Every day hundreds of millions of people capture what they see, hear, touch, and feel to a variety of storage media— like camera memory cards, cell phones, USB sticks, hard drives, external drives and CD-ROMs. Millions of them lose at least some of this digitally stored experiences daily. Every month over five million people search the web looking for ways to recover their lost photos, spreadsheets, and other important files. Because of the lack of advancements in data recovery techniques over the decades, not everyone of them can recover evertyhing they really need. Sadly, we have learned to live with what we couldn’t recover and blame ourselves for the loses.
Digital Assembly not only introduced a breakthrough technology to recover more data but also a new way of thinking about data recovery. SmartCarving is at the forefront of such a breakthrough technology.
Much like how a book chapter or a newspaper article is broken into multiple pages files stored on hard disks and memory cards are broken into blocks. Be it a vacation photo, a favorite song, or an important document it is first broken into blocks and each block is then written to available “free blocks” in a storage media. Each storage media also has a table of contents of sort. List of blocks that make up files stored in a media is maintained in this table. This table is reffered to as a file system. When you click on a photo to view or click on a song to play file system is consulted to put the blocks back together to display the photo or play the song.
Unlike a book or a newspaper, contents on a disk changes with time. Photos on a camera’s memory card are removed to make room for new ones. Documents in a hard drive are deleted to be replaced with new ones. When a file is deleted, the name of the file is marked as deleted in the file system and the corresponding blocks are added to the “free blocks” entry (See Figure Above). Blocks that contain the pixels that make up a photo or that contain the numbers that make up a spreadsheet are never removed from the disk. Contents of these blocks may remain on the disk long after the corresponding file is deleted. These remaining contents may be overwritten by the contents of a new file added to the disk.
Why do we delete files? To remove clutter, to make room for new files and sometimes, to err. Some data recovery programs simply look at the file system on a disk for files marked as “deleted” and simply recover these files by reading the corresponding blocks. Others, scan the entire disk or memory card looking for special markers that indicate beginnings and ends of files to simply carve a file out of blocks between these markers. These methods do not recover everything. If an entry in the file system is lost or when the blocks that make up a file are not contiguious on disk they fail to recover the corresponding file. Data recovery has been done this way for decades and those who lost the files thought some files are never to see the light of day ever again.
Digital Assembly introduced not only a new method but also a new way of thinking about data recovery. SmartCarving looks at file recovery as a giant jigsaw puzzle. Each block of a file is a piece of this puzzle. Recovering a file is like solving a jigsaw puzzle with tens of thousands of pieces. Recovering files from a disk or memory card is like solving multiple jigsaw puzzles of hundreds of millions of pieces simultaneously! A task that on the surface seems intractable has been made possible by an array of computer algorithms and sophisticated mathematical models. To our users all this simply means more recovery with less effort.