[TriLUG] how do USB disks and USB wifi cards work?

[Joseph Mack NA3T]

On Mon, 9 Jun 2008, David Brain wrote:

> Hi,
>
> Not quite - the 'drive like' behavior of USB devices is a standard
> (http://en.wikipedia.org/wiki/USB_mass_storage_device_class) so the
> kernel code just has to know how to talk that to make USB disks work.

I had assumed that the USB layer was like the transport 
layer in TCPIP, which could be a serial line, ethernet or 
fiber all of which presented the same interface to the layer 
above and which were interchangeable.

I'd assumed that USB, IDE and SCSI where interchangeable in 
the same way and that maybe USB could replace PCI or pcmcia 
as a bus.

> I do not believe there is a similar standard for 'network like
> devices' (which would be nice...).  So for a USB network device you
> are in the normal situation of needing to have a, normally
> vendor/chipset specific driver.

This seems like bad history being repeated. Is this a matter 
of no-one sitting down together and saying "we're all going 
to do it this way".

Joe

-- 
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
jmack (at) wm7d (dot) net - azimuthal equidistant map
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