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The interface is also known by the brand names of FireWire (Apple Inc.), i.LINK (Sony), and Lynx (Texas Instruments).

It is preferred over the more common USB for its greater effective speed and power distribution capabilities, and because it does not need a computer host. Perhaps more important, FireWire makes full use of all SCSI capabilities and has high sustained data transfer rates, a feature especially important for audio and video editors. Benchmarks show that the sustained data transfer rates are higher for FireWire than for USB 2.0, especially on Apple Mac OS X with more varied results on Microsoft Windows.

Historically, performance of 1394 devices may have decreased after installing Windows XP Service Pack 2, but were resolved in Hotfix 885222 http://support.microsoft.com/kb/885222/ and in SP3. Some FireWire hardware manufacturers also provide custom device drivers which replace the Microsoft OHCI host adapter driver stack, enabling S800-capable devices to run at full 800 Mbit/s transfer rates on older versions of Windows (XP SP2 w/o Hotfix 885222) and Windows Vista. At the time of its release, Microsoft Windows Vista supported only 1394a, with assurances that 1394b support would come in the next service pack.

However, while the IEEE 1394a and IEEE 1394b standards are compatible, FireWire 800's connector, referred to as a beta connector, is different from FireWire 400's alpha connectors, making legacy cables incompatible.

At this time USB 1.0 had a signaling speed of 12 and 1.5 Mbit/s (compared to 400 Mbit/s of IEEE-1394a (FireWire 400)) but cheaper implementations. Although high-speed USB 2.0 nominally runs at a higher signaling rate (480 Mbit/s) than FireWire 400, data transfers over S400 FireWire interfaces generally outperform similar transfers over USB 2.0 interfaces. Typical USB PC-hosts rarely exceed sustained transfers of 280 Mbit/s, with 240 Mbit/s being more typical. This is likely due to USB's reliance on the host-processor to manage low-level USB protocol, whereas FireWire delegates the same tasks to the interface hardware (requiring less or no CPU usage). For example, the FireWire host interface supports memory-mapped devices, which allows high-level protocols to run without loading the host CPU with interrupts and buffer-copy operations.

Specifically, RFC 2734 specifies how to run IPv4 over the FireWire interface, and RFC 3146 specifies how to run IPv6.

The system was designed for machine vision systems, libdc1394: IIDC/DCAM specifications but is also used for other computer vision applications and for some webcams. Although they are easily confused since they both run over FireWire, IIDC is different from, and incompatible with, the ordinary DV (Digital Video) camcorder protocol.

Labeling of the port varies by manufacturer, with Sony using either its i.LINK trademark or the letters 'DV'. Many digital video recorders have a "DV-input" FireWire connector (usually an alpha connector) which can be used to record video from a directly-connected DV camcorder ("computer-free").

While this enables high-speed and low-latency communication between data sources and syncs without unnecessary copying (such as between a video camera and a software video recording application, or between a disk drive and the application buffers), this can also be a security risk if untrustworthy devices are attached to the bus. For this reason, high-security installations will typically either purchase newer machines which map a virtual memory space to the FireWire "Physical Memory Space" (such as a Power Mac G5, or any Sun workstation), disable the OHCI hardware mapping between FireWire and device memory, physically disable the entire FireWire interface, or do not have FireWire at all.

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