[Beowulf] using two separate networks for different data streams

[Greg Lindahl]

On Mon, Jan 30, 2006 at 01:18:22AM -0500, Mark Hahn wrote:

> hmm, I had the impression that InfiniPath operated in either fast
> InfiniPath-to-InfiniPath mode, or in slow generic IB mode.  that is,
> that in "fast" mode, it was mostly just recycling IB phy layers.

Our fast mode is the moral equivalent to sending packets with unusual
ethertypes over Ethernet. That's still Ethernet; the standard allows
for such an extension. IB is similarly extensible.

The Cray XT3 is an example, I think, of a system which sends
non-IB-like packets over an IB physical layer. But I don't think the
details are public and I don't know much about the XT3.

-- greg