What is FireWire?

FireWire (IEEE 1394) Definition, Versions, and USB Comparison

Photo of an AmazonBasics IEEE 1394 4-Pin to 6-Pin FireWire Cable
AmazonBasics IEEE 1394 4-Pin to 6-Pin FireWire Cable. © Amazon.com
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IEEE 1394, commonly known as FireWire, is a standard type of connection for many different kinds of devices like digital video cameras, some printers and scanners, external hard drives and more.

The terms IEEE 1394 and FireWire usually refer to the types of cables, ports, and connectors that are used to connect these types of external devices to computers.

USB is a similar standard type of connection that is used for devices like flash drives (as well as printers, cameras, etc.).

The latest USB standard transmits data faster than IEEE 1394 and is more widely available. More on the differences between USB and FireWire below.

Other Names for the IEEE 1394 Standard

Apple's brand name for the IEEE 1394 standard is FireWire, which is the most common term you'll see when someone is talking about IEEE 1394.

Other companies sometimes use different names for the IEEE 1394 standard, too. Sony, for example, has dubbed the IEEE 1394 standard as i.Link, while Lynx is the name used by Texas Instruments.

More About FireWire & Its Supported Features

FireWire is designed to support plug-and-play, meaning that an operating system will automatically find the device when it's plugged in and will ask to install a driver to make it work.

IEEE 1394 is also hot-swappable, meaning that neither the computers that the FireWire devices are connected to, nor the devices themselves, need to be shut down before they're connected or disconnected.

All versions of Windows, from Windows 98 to Windows 10, support FireWire, as well as Mac OS 8.6 and later, Linux, and most other operating systems as well.

Up to 63 devices can connect via daisy-chain to a single FireWire bus, or controlling device. Check out this illustration of two external hard drives daisy-chained together to see what I mean.

The first hard drive connects to the computer, and the second one is plugged directly into the first.

Even if you're using devices that support different speeds, each of them can be plugged into the same bus and operate at their own maximum speeds. This is because a FireWire bus can alternate between varying speeds in real time, regardless of whether or not one of the devices is much slower than the others.

FireWire devices can also create their own peer-to-peer network for communicating. This ability means they won't use up system resources, like your computer's memory, but more importantly, it means that they can be used to communicate with each other without a computer at all!

One time where this might be really useful is a situation where you might want to copy data from one digital camera to another. Assuming they both have FireWire ports, just connect them together and transfer the data - no computer or memory cards required.

FireWire Versions

IEEE 1394, first called FireWire 400, was released in 1995. It uses a 6-pin connector and can transfer data at 100, 200, or 400 Mbps (depending on the FireWire cable used) on cables as long as 4.5 meters. These data transfer modes are commonly called S100, S200, and S400.

In the year 2000, IEEE 1394a was released, which provided improved features like a power-saving mode. IEEE 1394a uses a 4-pin connector instead of the 6 pins that exist in FireWire 400 because it doesn't include power connectors.

Just two years later came IEEE 1394b, called FireWire 800, or S800. This 9-pin version of IEEE 1394a supports transfer rates up to 800 Mbps on cables up to 100 meters in length. The connectors on the cables for FireWire 800 are not the same as those on FireWire 400, which means the two are incompatible with each other unless a conversion cable or dongle is used.

In the late 2000's, FireWire S1600 and S3200 were detailed that supported transfer speeds as fast as 1,572 Mbps and 3,145 Mbps.

However, so few of these devices were released that they shouldn't even be considered as part of the "timeline" of FireWire developments.

In 2011, Apple began replacing FireWire with the much faster Thunderbolt and, in 2015, at least on some of their computers, with USB 3.1 compliant USB-C ports.

What Are the Differences in FireWire and USB?

FireWire and USB are similar in purpose (they both transfer data) but differ significantly in areas like availability and speed.

You definitely won't see FireWire supported on nearly every computer and device like you do with USB. Most modern computers don't have FireWire ports built in, meaning they'd have to be upgraded to do so... something that costs extra and that there may not even be room for the computer to do.

The most recent USB standard is USB 3.1, supporting transfer speeds as high as 10,240 Mbps. This is much faster than the 800 Mbps that FireWire supports.

Another advantage that USB has over FireWire is that USB devices and cables are generally cheaper than their FireWire counterparts, no doubt due to how popular and mass-produced USB devices and cables have become.

As I mentioned above, FireWire 400 and FireWire 800 use different cables that are not compatible with each other. The USB standard, on the other hand, has always been very good about maintaining backward compatibility.

One advantage of FireWire devices, as I mentioned already, is that they can be daisy-chained together. This can't be said for USB devices, which require a computer to process the information after it leaves one device and enters another.