http://www.usb-ware.com/firewire-vs-usb.htm
Question: If Hi-Speed USB 2.0 is a 480 Mbps interface and FireWire is a 400 Mbps interface, how can FireWire be faster?
Answer: Differences in the architecture of the two interfaces have a huge impact on the sustained throughput.
* FireWire, uses a "Peer-to-Peer" architecture in which the peripherals are intelligent and can negotiate bus conflicts to determine which device can best control a data transfer
* Hi-Speed USB 2.0 uses a "Master-Slave" architecture in which the computer handles all arbitration functions and dictates data flow to, from and between the attached peripherals (adding additional system overhead and resulting in slower data flow control)
* Read and write tests to the same IDE hard drive connected using FireWire and then Hi-Speed USB 2.0 show:
*Read Test:*
5000 files _(300 MB total)_ *FireWire was 33% faster than USB 2.0*
160 files _(650MB total)_ *FireWire was 70% faster than USB 2.0*
*Write Test:*
5000 files _(300 MB total)_ *FireWire was 16% faster than USB 2.0*
160 files _(650MB total)_ *FireWire was 48% faster than USB 2.0*