Data Backup Digest

SD cards serve as read-only memory that is often used in portable devices, including digital cameras, MP3 players and cell phones. Just like with hard drives, SD cards also support various file systems. Each available file system has its advantages as well as disadvantages, although the relatively new Extended File Allocation Table architecture, also known as exFAT, has become commonly accepted by industry professionals as one of the best file systems available for consumer SD cards.

History

Although it is still considered relatively young in terms of technology, the exFAT file system was actually introduced in November 2006. Created and developed by Microsoft, the technology was originally integrated into Windows XP and Windows Server 2003 via update KB955704. It is supported in every version of Microsoft Windows since.

Advantages

exFAT has a number of advantages over both FAT32 and NTFS. One of the biggest and most noticeable differences is exFAT's elimination of the 4 GB limit placed on file sizes. Although NTFS allows for files larger than 4 GB, the file system cannot be written by the Mac OSX operating system; it is only readable. Furthermore, this increased file size offers plenty enough room to store large files, including games, videos and music. File cluster sizes have also been increased to 32 MiB, which ultimately reduces system overhead while increasing efficiency.

Microsoft is also steadily introducing new features and innovations to the exFAT file system. Support for access control lists, as well as support for UTC timestamps, is both included in Windows Vista SP2 as well as Windows CE 6. Access control lists allow you a greater level of file security by giving you the option of specifying which specific users or processes can access certain objects or files, while UTC timestamps let you synchronize the file creation and modification dates with the Coordination Universal Time standard.

Disadvantages

One of the biggest disadvantages associated with the exFAT file system is compatibility. While Windows and Mac OS X operating systems fully support exFAT, some SD cards simply do not. Moreover, some hardware devices, particularly older ones, may not be able to read the exFAT file architecture. This is primarily due to Microsoft not releasing an official exFAT specification for industry use, which prevents many third-party vendors from obtaining proper licensing.

More operating systems and devices are beginning to embrace the exFAT technology, however. In fact, some of the most recent Linux distributions include full support for exFAT, although the file system is supported only in the user space and not the Linux kernel itself. These limitations have severely restricted the popularity of the format, though the benefits of the file system itself cannot be denied.

Conclusion

When it comes to choosing the file system for your SD cards, exFAT is the obvious choice – given your devices support it. Combining the best elements from both FAT32 and NTFS, the exFAT file architecture almost serves as a hybrid of the two. There is no doubt we will be hearing much more from Microsoft regarding the future of exFAT as more vendors acquire the proper licensing and when an increased number of consumer devices begin to support the use of the improved file architecture.