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zurek106 · Jul 22, 2002, 09:26 PM

For peripherals, what is faster, USB 2 or Firewire?

Timothy Maxwell · Jul 22, 2002, 11:05 PM

<blockquote>quote:<hr />Originally posted by zurek106:
For peripherals, what is faster, USB 2 or Firewire?<hr /></blockquote>I believe the speed of both are about the same. USB 2 seems to have a slight but barely measureable edge.

Joost · Jul 23, 2002, 12:31 AM

<blockquote>quote:<hr />Originally posted by Timothy Maxwell:
 <blockquote>quote:<hr />Originally posted by zurek106:
For peripherals, what is faster, USB 2 or Firewire?<hr /></blockquote>I believe the speed of both are about the same. USB 2 seems to have a slight but barely measureable edge.<hr /></blockquote>...but it's not so good at sustaining speeds and it's CPU-bound.

For external hard drives, this is worth a look:

<a href="http://www.barefeats.com/fire26.html" target="_blank">http://www.barefeats.com/fire26.html</a>

ratlater · Jul 23, 2002, 01:31 AM

That test is a good example of results I've seen all over the web. USB 2.0 plain old fashioned sucks. It is supposed to be faster in theory, but in reality it is much slower.

-matt

Ken_F2 · Jul 23, 2002, 02:47 AM

<blockquote>quote:<hr />That test is a good example of results I've seen all over the web. USB 2.0 plain old fashioned sucks. It is supposed to be faster in theory, but in reality it is much slower.<hr /></blockquote>Well, the USB 2.0 support in the first one or two chipsets that had it...kind of sucked. It's much improved since as chip companies have learned how to properly implement USB 2.0. The bearfeats example isn't particularly good, because the MacOS and its drivers aren't at all optimized for USB 2.0 transfers (obviously that will change when Apple implements USB 2.0).

On a particular full scan with my Epson scanner, I'd say that both USB 2.0 and Firewire are both within 2-3 seconds of 40 seconds (so not much difference), while USB 1.0 full scans take closer to 2 minutes. Basically, I can't tell any difference between USB 2.0 and Firewire on my system, but both are a massive improvement over USB 1.0.

[ 07-23-2002, 03:49 AM: Message edited by: Ken_F2 ]

chabig · Jul 23, 2002, 09:58 AM

Remember too, that firewire was designed to do one thing very well--transfer data at high speed.

USB was originally designed for low speed transfer. The fact that they are now pursuing higher speed is solely related to marketing, and a strong "not invented here" syndrome at Intel. USB 2.0 is a bastardized spec that can't deliver on its promises. That's why you never get the advertised 480Mbps speed.

Jul 23, 2002, 11:43 AM

Andy Ihnatko's beefs about USB2:

* USB 2.0's top speed is theoretically higher than FireWire's, but I've yet to have a USB 2.0 drive outperform a FireWire drive in reading and writing data. FireWire performance is more or less a flat line all the way across the chart (well, duh; isochronous data rates are part of the FireWire spec) while the USB drive keeps dipping and recovering. And FireWire is still just plain better in a wider range of applications. Most users won't really notice the speed difference, but if you're operating a big database, you're gonna regret keeping it on a USB 2.0 drive.

* The 2.0 spec can deliver enough speed for high-performance devices, but it still doesn't deliver nearly enough power. Unless a USB device is something simple (like a mouse) it'll need its own power supply. FireWire sends enough oomph across the connection to power nearly anything; a FireWire drive frees you from the tyranny of having to carry a power brick that weighs more than the drive itself and forces you to crawl under your desk to the power strip from time to time.

* USB works only in a master-slave configuration; one device has to be calling the shots. FireWire is peer-to-peer, which makes it more flexible. This feature saved my life a couple of months ago. I was in someone's office and desperately needed a Net connection but couldn't use my host's ethernet. So I hooked up my XP notebook to a desktop via FireWire, used XP's nifty built-in feature for bridging two networks and bango: FireWire to Ethernet to the Internet.

CIA · Jul 24, 2002, 09:09 AM

As SpinyNorman said, USB and Firewire are close in many ways, but also rather different:
First off, all three are hot swap enabled. Meaning you can plug in and unplug devices at anytime, without having to powerdown the computer.

USB 1.1 -- Up to 127 devices are supported with hubs and daisy chains. Due to the fact that some devices reserve USB bandwidth, the practical maximum of devices is less than the theoretical maximum. The USB connection is of course serial, and the current version (1.1) runs with a maximum throughput of 12 Mbits/second (1.5 Mbytes/second), which is shared by all devices. There is also a slower-speed, 187.5 kbytes/second mode available for very slow devices, such as keyboards. The USB bus has enough juice to power small devices (floppy drives, Compact Flash Card Readers, etc) without the need for external power adaptors, but the devices must be plugged directly into the computer or directly into a powered hub to use this feature. (The same goes for firewire bus powered devices)

USB 2.0 -- USB 2 devices are backwards compatable with 1.1 devices, Maximum throughput of 480 Mbits/second. This bandwith is shared with all devices on the USB chain of course. I believe, but am not certain. That USB 2 slows down when on a mixed network, meaning if you have a USB 1.1 device and a USB 2 device on the same chain, the overall speed slows to USB 1.1 speeds. This may have changed with newer USB chipsets. Also, USB is CPU dependant, IEEE-1394/Firewire/i.Link is not. USB2 is great if you only have or 2 things hooked up to it, but performance drops off quickly after that. I don't know if the 127 device limit has increased with USB 2, but few people have a need for 127 (or more!) USB devices anyway, so this is not a big deal. I don't know if USB2 can be used for networking, I know on a mac at least, USB 1.1 can not.

IEEE-1394/Firewire/i.Link devices share up to 400 Mbits/second of bandwidth. It is based loosely on the SCSI-3 standard (which is why Firewire hard drives show up as SCSI in Drive Setup) The Firewire standard is much better at sharing all that bandwith, so performance loss is slim when multiple devices are attached. The firewire standard is scaleable, meaning 800 Mbits/second (Very soon!) and I've heard up to 3.2 Gbits/second (who knows when) are possible, with backwards compatability. I don't know what performance loss occurs on a mixed network of 800 Mbits/second and 400 Mbits/second devices. The 800 Mbits/second standard was recently finalized and there are few, if any products on the market that are 800 Mbits/second capable. Firewire can carry power over it's cables, so you can buy hard drives that are "Bus Powered" that do not require external power supplys. Like USB, Firewire bus powered devices must be plugged into a firewire Hub or directly into the computer to use bus power features. Firewire can be used for networking, but I don't know much about this. Also, I believe you can only connect 63 firewire devices in a chain. This is still more then any average person will ever see though.

From the USB.org website:

Serial port: 115kbits/s (.115Mbits/s)
Standard parallel port: 115kBYTES/s (.115MBYTES/s)
Original USB: 12Mbits/s (1.5MBYTES/s)
ECP/EPP parallel port: 3MBYTES/s
IDE: 3.3-16.7MBYTES/s
SCSI-1: 5MBYTES/s
SCSI-2 (Fast SCSI, Fast Narrow SCSI): 10MBYTES/s
Fast Wide SCSI (Wide SCSI): 20MBYTES/s
Ultra SCSI (SCSI-3, Fast-20, Ultra Narrow): 20MBYTES/s
UltraIDE: 33MBYTES/s
Wide Ultra SCSI (Fast Wide 20): 40MBYTES/s
Ultra2 SCSI: 40MBYTES/s
IEEE-1394: 100-400Mbits/s (12.5--50MBYTES/s)
Hi-Speed USB 2.0: 480Mbits/s
Wide Ultra2 SCSI: 80MBYTES/s
Ultra3 SCSI: 80MBYTES/s
Wide Ultra3 SCSI: 160MBYTES/s
FC-AL Fiber Channel: 100-400MBYTES/s