Re: GigE (was Re: [Discuss-gnuradio] DSP based SDR)

[Marcus D. Leech]

Harald Welte wrote:
> 
> On Tue, Jun 21, 2005 at 04:10:35PM -0700, John Gilmore wrote:
> > I'm picking up the Gigabit Ethernet conversation from a few weeks ago.
> 
> great :)
>
> 
> I didn't state (or at leat want to state) that it was impossible to
> achieve multiple-gigabit data rates with the Linux network (or even
> TCP/IP) stack.
> 
> I just think that it is a horrible waste of cpu cycles and memory
> bandwidth, when all you want is to get large amounts of data from a
> local (cloe to the computer) device into an userspace application.  This
> is especially true if your userspace application is a cpu hog like
> digital signal processing algorithms ;)
> 
>

I'll point out the obvious here.  If it's purely-local, then there's no need to
  deal with the TCP/IP stack--raw ethernet frames would work just fine, and
  cut-out much of the processing you're complaining about.

I'd configure things with a 1GigE card for the radio data grabber, and another
  card for my real network traffic.

-- 
Marcus Leech                            Mail:   Dept 1A12, M/S: 04352P16
Security Standards Advisor        Phone: (ESN) 393-9145  +1 613 763 9145
Advanced Technology Research
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