U3
From Wikipedia, the free encyclopedia
- For the airline using U3 as its IATA designator, see Avies.
| U3 LLC. | |
 |
|
| Type of Company | Private |
|---|---|
| Founded | 2004 |
| Headquarters | Redwood City, CA |
| Industry | Computer |
| Slogan | Your digital universe in your pocket. |
| Website | www.u3.com |
U3 LLC is a joint venture that is backed by Sandisk and M-Systems. U3 is responsible for the development of a proprietary application design specification created for Microsoft Windows operating systems so that applications can be executed directly from a specially formatted USB flash drive. Applications are allowed to write files or registry information to the host computer, but this information must be removed when the flash drive is ejected.
USB flash drives adhering to the U3 specification are termed "U3 smart drives" by U3.com. "U3 smart drives" differ from traditional USB flash drives because they come preinstalled with the U3 Launchpad, which emulates the Windows OS start menu, and controls program installation.
Contents |
[edit] The U3 platform
[edit] U3 Launchpad
The U3 Launchpad is a program manager that is preinstalled on every U3 smart drive, and is set to autoplay on insertion. [1] A partition with the U3 Launchpad pretends to be a CD/DVD-ROM device in order to add USB mass storage device autoplay functionality on pre-Windows XP SP2 systems, or systems whose USB autoplay has been intentionally disabled.
The program is made to work with Windows 2000 Service Pack 4 and above. No Launchpad program exists for the Mac OS or Linux platforms. [2]
[edit] U3 applications
To be fully U3 compliant, an application has to be programmed to clean up its own data from the local machine. It must also be packaged in U3's special program format. U3 applications will only run from a U3 device.
[edit] APIs
The U3 APIs allows U3 Programs lower-level access to USB flash drive.
[edit] Hardware
U3 smart drives are traditional USB flash drives with a specific setup:
- Disk Management shows two drives, one drive has a CDFS partition with the autorun and LaunchPad, and the other drive has a FAT partition that includes a hidden SYSTEM folder with your installed applications.
- Optional: U3 Compliant Applications Preloaded
Hardware manufacturers can get the hardware development kit by emailing licensing@u3.org. [3]
[edit] Compatibility
The U3 Launchpad and U3 Applications will only run on newer Microsoft Windows Operating Systems (Microsoft Windows 2000 with Service Pack 4 and Windows XP). U3 works for the newest version, Windows Vista. Data will continue to be accessible from any OS capable of reading from USB Mass Storage Devices, unless the U3 device is password protected [4]. "If the OS in question can normally see ordinary USB flash drives, then the U3 smart drive removable mass storage area (domain) should still be available for standard file system activities unless it is a private area protected by a password."
[edit] Developer resources
Information on building U3 compliant applications, and the U3 software development kit, are available to registered developers at the official U3 website. Individuals must register (as a company) to download the SDK, or participate in the forums. [5]
[edit] Benefits
- Software can be taken with all its personalised settings to any computer running a compatible version of Microsoft Windows, with no need to install the software if not already there, or to use different settings and options, and no need for administrator access privileges.
- Software is available from the U3 site, including amongst others Trillian, OpenOffice.org, Filezilla (FTP app), Firefox (Internet Browser), Sudoku (Game), Skype (Phone calls from your computer).
- Programs are run from the Launchpad, functionally similar to the Windows Start menu familiar to most users of Windows XP.
- New software can be downloaded to a U3 flash drive without the requirement for administrative privileges on the host computer.
- Many U3 drives come with virus protection software which gives protection against being infected by or spreading computer viruses.
- Some popular free portable application programs available at PortableApps.com for non-U3 flash drives have been adapted for use with U3 drives. They are available at the web sites of U3 and PortableApps.com.
[edit] Criticisms
Several criticisms have been made of the U3 platform. These criticisms are:
- Closed Platform - The U3 platform is closed and only open to vendors that U3 chooses to admit.
- Lack of Reliability - On some systems, U3's attempting to start up will cause the computer to freeze.
- Stress on drives - USB flash drive technology was not originally designed to handle the large number of write operations associated with running software
- Not Uninstallable - The U3 Launchpad cannot easily be uninstalled by an end-user. U3 responded to this criticism by making available uninstall software on their website.[6] This is due to Best Buy's Geek Squad who in early 2006 raised the issue of not being able to uninstall U3, and got them to write an uninstaller for first the Geek Squad branded drives and then all the U3 drives. The uninstaller doesn't work in all cases. As of November 2006, U3 drives come with an uninstaller on the USB drive itself. But the uninstaller requires Windows 2000 or XP, and requires installing proprietary software on the computer before being able to remove the U3 features from the flash drive.
- Leaves Traces on Host PC - The U3 platform sometimes leaves behind files on a user's PC. This mainly occurs when the drive is improperly removed.
- Data Security - Most U3 drives on the market feature a security lock within the U3 Launchpad. This loads the CD partition first and requires a password to be entered, otherwise the data partition will not load. The drive is supposed to seal itself after a certain number of invalid password entries, requiring a reformat.[7] Additionally, since the data partition is not encrypted, an end-user's data may not actually be secure as the U3 CD-ROM partition can be easily be used to store any program.[8]
- Latest versions of Nero's InCD tend to be incompatible with U3. Since u3 mimics a CD drive, InCD tries to operate on it and freezes the system. The only solution is to uninstall InCD or get an older version of InCD. InCD is used for adding drag and drop functionality to CD-RWs and DVD-RWs.1
- Compatibility - Some non-Windows users and users of older versions of Windows (pre-Windows 2000) experience problems using U3 drives, apparently because the emulation of a "vanilla" USB drive is imperfect.
- Problems - Where a user has insufficient privileges he may run into problems getting the launcher to work. In such a case the launcher might actually prove a hinderance to using the device
[edit] See also
[edit] External links
[edit] Official
- U3 website (This website isn't very reliable and may be down.)
- U3 Knowledge Base
- U3 Software Central
[edit] Reviews and overviews
- PC Magazine reviews of the U3 Launcher, and programs (has screenshots)
- Freeware site applauds the simplification of "portable" application development
- U3 Newbie Guide
[edit] Developer resources
- U3 SDK (requires registration. individuals can register as companies)
- U3 Platform Overview (pdf)
