Inert Detritus The Internet's dust bunnies

20 September 2007 @ 10am

USB 2.0, and FireWire’s Slow Demise

USB 2.0 ver­sus FireWire 400 has been an inter­est­ing bat­tle to fol­low. The orig­i­nal iPod was a FireWire-only device: USB 1.1 was too dog slow to even think about using it to fill a 5 GB hard dri­ve. FireWire first appeared on a Mac in Jan­u­ary of 1999, while USB 2.0 did­n’t even appear on an Apple machine until 2003.

For hard dri­ve trans­fers, FireWire is inar­guably bet­ter: it had high sus­tained through­put, ded­i­cat­ed hard­ware chipsets, much more pow­er com­ing over the (option­al) two pow­er pins, and mem­o­ry-mapped trans­fers which allowed the host com­put­er to stay out of the way dur­ing data trans­fers. USB 2.0, while tech­ni­cal­ly spec­i­fied with a high­er pos­si­ble band­width, was nev­er able to sup­port the time-sen­si­tive, asyn­chro­nous data trans­fers that FireWire allowed. FireWire was king of the con­sumer realm for hard dri­ves, burn­ers, scan­ners, and DV cam­eras, espe­cial­ly on the Mac.

But USB 2.0 had one big thing going for it: it was back­wards com­pat­i­ble with USB 1.1. Had a 2.0 device on a 1.1 com­put­er? It worked, but it ran slow. 1.1 device plugged a 2.0 port? You did­n’t even know the dif­fer­ence. USB 2.0, instead of being the new kid on the block, all ready had an “installed base” of mil­lions of devices plugged into mil­lions of machines. Sure, the speeds would­n’t be 2.0, but they worked, and that was good enough for most users.

And so, with the inclu­sion of USB 2.0 on Macs start­ing in 2003, the near-ubiq­ui­ty of them on the PC side, Apple vot­ed in 2005 to drop FireWire sup­port from the iPods, pick­ing up a small­er form fac­tor along the way (those sep­a­rate hard­ware chipsets take up space, no mat­ter how small you make them). FireWire slow­ly fell by the wayside.

I’m espe­cial­ly glad that from day one, I always bought dual-con­nec­tion FireWire/USB 2.0 hard dri­ve enclo­sures. Aside from mak­ing trans­fers from Mac to PC or back easy with­out hav­ing to have FireWire sup­port on the PC side, it future-proofed things. If/when USB 2.0/3.0 took off, I knew I’d be able to plug the dri­ves in and run with them, and not have to fret about the con­nec­tion I was using.

Sad­ly, USB 3.0 will fin­ish the job start­ed by USB 2.0: the com­plete obso­le­tion of FireWire. As a high­er speed, 2.0‑compatible con­nec­tor (cur­rent­ly planned with a dual-use optical/wired cable, capa­ble of 10x high­er speeds than 2.0, and pos­si­bly, nay, prob­a­bly 1.1‑compatible), it has all the mak­ings of the next suc­cess­ful hard­ware pro­to­col to con­nect devices to the computer.

(Wikipedia, as usu­al, has great arti­cles for FireWire and USB.)