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(computer science)
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


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Officially the IEEE 1394 High Performance Serial Bus (HPSB), FireWire is a high-speed interface developed and promoted mostly by Apple for video transmission. Introduced in 2000, FireWire was added to camcorders and a variety of A/V equipment. Even early iPods could connect via FireWire. However, on modern camcorders, FireWire was replaced with USB, HDMI and other video outputs.

FireWire 400 and 800
FireWire 400 was limited to a distance of 4.5 meters. In 2003, FireWire 800 increased the range to 100 meters and doubled the transfer rate. FireWire supported 63 devices, real-time data transfer, hot swapping and simultaneous multiple speeds. The faster 1600 and 3200 versions never got into production. See PC data buses.


  FW400     400 Mbps

  1394b - 100 METER CABLE LENGTH

  FW800     800 Mbps
  FW1600   1600 Mbps
  FW3200   3200 Mbps

FireWire Sockets and Compatibility
FW800 was backward compatible with FW400. One end of a "bilingual cable" had an FW800 plug, while the other end was FW400. Sony's i.Link was a miniaturized socket that connected to cables with i.Link, FW400 or FW800 at the other end.

FireWire 400 and 800 Sockets
The two FireWire sockets are easily identified.

Dual Mode FW/USB
This earlier external hard drive connected to the computer via FireWire or USB, whichever cable was plugged in.
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References in periodicals archive ?
"FireWire has proved itself to be extremely popular, and Apple has responded with a terrific new MacBook Pro with 1394b," said James Snider, executive director, 1394 Trade Association.
Notice that 1394b is limited to ~61MB/sec due to the overhead of the interface of approximately 20Mbytes/sec.
New features on the P65, which weighs 4.4 pounds include voice recording--up to 30 seconds with each image--utilizing Bluetooth wireless technology, with a cordless earpiece eliminating all cable connections; and FireWire (IEEE 1394b) connectivity, enabling the transfer of digital video at up to 800 megabits per second, plus USB and IrDA connectivity
The DMS is based on the IEEE 1394b standard, which is designed to run high-speed audio, video, and Ethernet transmissions up to roughly 100 meters from the source in a residence.
In addition Agere intends to accelerate development of chip products for 1394b applications while also continuing to provide 1394a chip systems.
Completion of the updated 1394b specification, which avoids some of the technology licensing issues that have plagued the emerging standard, is expected by late this year.
According to the 1394 Trade Association, the 1394b bus provides guaranteed quality of service with predictable latencies for more than 70 devices associated with communications systems, weapon systems, engine controls, and flight controls.
The SiI 3132 is an ideal solution for enabling external SATA, providing much faster data transfer rates than USB 2.0 (480 Mb/s) and Firewire 1394b (800Mb/s) and enabling high-performance solutions through port multiplier support."
Some of the host bus speeds are 12MBps for USB 1.0, 40MBps for UltraSCSI, 50MBps for 1394a, 60MBps for USB 2.0, 80MBps for Ultra2 SCSI, 100MBps for 1394b, 150MBps SATA Gen1, 160MBps Ultra160 SCSI, 300MBps for SATA Gen2, 320MBps Ultra320 SCSI.