1394-firewire

FireWire is a proprietary name of Apple Computer for the IEEE 1394 interface. It is also known as i.Link or IEEE 1394 (although the 1394 standard also defines a backplane interface). It is a personal computer (and digital audio/digital video) serial bus interface standard, offering high-speed communications and isochronous real-time data services. FireWire has replaced Parallel SCSI in many applications due to lower implementation costs and a simplified, more adaptable cabling system. IEEE 1394 has been adopted as the High Definition Audio-Video Network Alliance (HANA) standard connection interface for A/V component communication and control.
Almost all modern digital camcorders have included this connection since 1995. Many computers intended for home or professional audio/video use have built-in FireWire ports including all Apple, Dell and Sony laptop computers currently produced. FireWire was also an attractive feature on the Apple iPod for several years, permitting new tracks to be uploaded in a few seconds and also for the battery to be recharged concurrently with one cable. However, Apple has eliminated FireWire support in favor of USB on its newer iPods due to space constraints and for wider compatibility.
Contents[hide]
1 History and development
2 Technical specifications
2.1 Operating system support
2.2 Node hierarchy
3 Standards and versions
3.1 FireWire 400
3.2 FireWire 800
4 Networking over FireWire
5 Security issues
6 Precautions
6.1 Hot Plug precautions
7 See also
8 References
9 External links
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[edit] History and development

A 6-Pin FireWire 400 connector
FireWire is Apple Computer's name for the IEEE 1394 High Speed Serial Bus. It was initiated by Apple and developed by the IEEE P1394 Working Group, largely driven by contributors from Apple, although major contributions were also made by engineers from Texas Instruments, Sony, Digital Equipment Corporation, IBM, and SGS Thomson (now STMicroelectronics).
Apple intended FireWire to be a serial replacement for the parallel SCSI bus while also providing connectivity for digital audio and video equipment. Apple's development was completed in 1995. As of 2006, IEEE 1394 is currently a composite of three documents: the original IEEE Std. 1394-1995, the IEEE Std. 1394a-2000 amendment, and the IEEE Std. 1394b-2002 amendment (there is a 1394c amendment that provides support for 800 Mbit/sec operation over 100 m of Category 5 unshielded twisted pair cable that will be published soon).
Sony's implementation of the system is known as i.Link, and uses only the four signal pins, discarding the two pins that provide power to the device in favor of a separate power connector on Sony's i.Link products.
The system is commonly used for connection of data storage devices and digital video cameras, but is also popular in industrial systems for machine vision and professional audio systems. It is used instead of the more common USB due to its faster effective speed, higher power-distribution capabilities, and because it does not need a computer host. Perhaps more importantly, FireWire makes full use of all SCSI capabilities and, compared to USB 2.0 High Speed, has higher sustained data transfer rates, a feature especially important for audio and video editors.
However, the small royalty that Apple Computer and other patent holders have initially demanded from users of FireWire (US$0.25 per end-user system) and the more expensive hardware needed to implement it (US$1–$2) has prevented FireWire from displacing USB in low-end mass-market computer peripherals where cost of product is a major constraint.
According to Michael Johas Teener, original chair and editor of the IEEE 1394 standards document, and technical lead for Apple's FireWire team from 1990 until 1996:[citation needed]

The original FireWire project name was "Chefcat", the name of Michael Teener's favorite coffee cup. The standard connectors used for FireWire are related to the connectors on the venerable Nintendo Game Boy. While not especially glamorous, the Game Boy connectors have proven reliable, solid, easy to use and immune to assault by small children.
FireWire is a trademark of Apple Computer, Inc. The trademark was filed in 1993. The "FireWire" name was chosen by a group of engineers socializing before Comdex 1993, just before the project was about to go public. IBM, Apple, Texas Instruments, Western Digital, Maxtor and Seagate were all showing drives, systems and other various FireWire support technology. The marketing forces behind the FireWire project had originally considered a name like "Performa".
FireWire won the "most significant new technology" award from Byte Magazine at the Comdex 1993 show.
During the period they participated with the IEEE p1394 working group, Apple proposed licensing all of their blocking patents for US$3,000, a one time fee only for "the point of first use" or the integrated circuits that implement the protocols. Furthermore, there was a discount if a contribution was made to the IEEE undergraduate scholarship fund. Under that agreement, the IEEE agreed to include the appropriate patents in the standard.
Apple never intended to charge for the use of the name "FireWire". It could be used by any party signing an agreement to use the name for a product that was compliant with IEEE 1394-1995, the original version of the standard. Steve Jobs was convinced that Apple should ask for US$1 per port for the patents that became part of the standard. The argument was that it was consistent with the MPEG patent fees.
The fallout from charging US$1 per FireWire port was significant, particularly from Intel. Intel had sunk a great deal of effort into the standard with the improved 1394a-2000 standard being partially based on work contributed by Intel. A group within Intel used this as a reason to drop 1394 support and bring out the improved USB 2.0 instead.
Simultaneously, Sony and the other backers of the technology noted to Apple that they all had patents too and were entitled to per-port royalties. Under these circumstances, Apple would have to pay roughly US$15 per port to the other FireWire technology developers. The end result was the creation of the "1394 Licensing Authority", a body which charges everyone US$0.25 per end-user system (like a car or computer) that uses any 1394 technology