IEEE-1394 is the rather bland name for a relatively new, high-speed serial
interface that has actually been around in one form or another for many years. In some
ways, the name is the most confusing aspect of this technology. It was originally
developed by Apple, who called it FireWire; this name became popular, but Apple
owns the rights to it, and many companies refused to pay to license the name. So then
everyone started to refer to it by the standard number assigned it by the IEEE, which formally published the interface
as a standard in 1995. To further muddle the issue, Sony then created its own marketing
term for the interface, i.Link.
IEEE-1394 is defined part of the SCSI-3 family of related
standards, and was at one point sometimes called "serial SCSI". It is, in
fact, a type of SCSI, based on the broad converage of SCSI-3, which goes beyond regular
SCSI to cover several similar, "SCSI-like" technologies. In terms of signaling
and some aspects of operation, IEEE-1394 really can be thought of as "serial
SCSI".
In terms of configuration and how it is used in the PC however, IEEE-1394 is better
thought of as "USB, only faster". (Or alternately, USB
is IEEE-1394, only slower. ;^) ) It is a serial interface that supports dozens of
daisy-chained devices, hot-swapping, and plug-and-play. However, instead of USB's 12
Mbits/second maximum transfer rate, IEEE-1394 supports up to 400 Mbits/second. Sounds
good, right? In fact, it does; when originally introduced, IEEE-1394 had considerable
promise, and there were some analysts who thought it would eventually become a major
player in the mainstream hard disk interface market. For example, it is not as fast as
high-speed implementations of SCSI, but is considerably simpler to implement, and doesn't
suffer from the speed limitations of USB.
In reality, though, IEEE-1394 still has not taken off as a storage interface within the
PC. There could be any number of reasons for this, but as of 2000, IEEE-1394 is not a
major player in the storage industry. Some systems are now equipped with this interface,
and a variety of storage devices are made for it, so it is a viable option if your system
supports it, or if you wish to add support for it. IEEE-1394 does continue to grow in
popularity in a variety of specialty markets, especially digital video, where it has
established quite a following. It may well become the next big interfacing standard for
consumer electronics devices like camcorders and VCRs. As for the PC world, the future is
uncertain, and the creation of the new, faster USB 2.0 standard
continues to keep the waters cloudy.
Note: For more information
on IEEE-1394, see the web site of the IEEE-1394 trade
association.
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