FireWire

Definition - What does FireWire mean?

FireWire is a high-speed real-time interface for serial bus and isochronous/synchronous data transfer between enabled devices.

Known for its high-performance, FireWire is used with digital audio/video, camcorders, home entertainment applications, central processing units (CPU) and personal computers (PC) and offers sustained transfer rates of over 3200 Mbits/s.

In 1986, Apple initiated FireWire as its main communications interface as a version of the Institute of Electrical and Electronics Engineers (IEEE) IEEE 1394 standard. FireWire was commercially released in the mid-1990s.

FireWire is also known as IEEE 1394, i.LINK and Lynx.

Techopedia explains FireWire

FireWire is used for audio-video (A/V) communication and built into most Apple operating systems. It is available in wireless, fiber optic, and coaxial isochronous protocol versions.

FireWire features include:

  • Plug and socket connector capability for up to 63 devices with data transfer rate (DTR) speeds up to 400 Mbps
  • Peer-to-peer (P2P) device communication networking without central processing unit (CPU) or system memory
  • Plug-and-play support, which allows operating systems (OS) to automatically detect and configure new peripherals without system shutdown
  • Hot swapping, which enables component removal and replacement without system shutdown

The IEEE 1394 port is accessible via motherboard or expansion card, but most motherboard manufacturers provide Universal Serial Bus (USB) support only.

IEEE 1394 DTRs are follows:

  • Isochronous data: Transferred during regular and uniformly intervals and simultaneously transmits varied data types over one circuit. Isochronous transfer of multimedia application data reduces buffering requirements by enabling continuous data flow.
  • Asynchronous data: Operates independent of other processes and is mostly used for load and store applications. Allows independent data transfer until interrupts occur.

IEEE 1394 is comprised of two levels:

  • Backplane bus: Electrical circuit board (ECB) that enables device connectivity and supports 12.5, 25 or 50 Mbps DTR.

  • Point-to-point interface: Serial cable for device communication and supports 100, 200 or 400 Mbps DTR.


    Firewire could become supeseded by the faster USB bus which in version 3.0 can reach speeds of up to 5 Gbits/s. As Apple includes USB this in its devices now, it is rapidly becoming the forerunner in this convergent technology. The main differecnce is that FireWire is a Peer-Peer communications standard whereby USB requires CPU time and a Bus Mastering device.

    There are many electronic items that rely on firewire interfaces, particularly in the realm of Digital Video, with most camcorders and many other associated electronic devices still bearing a firewire socket.

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