Re: [Discuss-gnuradio] Timestamps, data rates

[Eric Blossom]

On Thu, Apr 16, 2009 at 08:34:25AM -0700, Johnathan Corgan wrote:
> 
> Similar issues exist on the transmit side.

Actually they are quite different.  When we assert flow control, we flow
control _everything_ upstream between the USRP2 and the host.  Unless
you want your network to die, die, die, don't put a switch between
the USRP2 and the host if you are transmitting, and for sure, don't
plug anything else into the switch.

You may find corner cases where it might work, but it's highly
dependent on what kind of switch, how much buffering it has, how the
switch was instructed to negotiate flow control etc.  There are big
portions of the Internet universe that consider it "evil" for an end
point to assert flow control.  That's what we do.

For all the gory details on this, see a good reference on Gigabit
ethernet flow control.  I found Rich Seifert's, "Gigabit Ethernet:
Technology and Applications for High-Speed LANS" useful.  You could
also read the GigE ethernet spec.

Eric