RE: Towards Consensus on TCP Connections

[Peter Johansson <PJohansson@acm.org>]

At 11:14 AM 8/11/00, Douglas Otis wrote:

>Firewire does not scale and has a limited reach.

Doug, I take exception to the first part of your statement, both because I 
believe that IEEE 1394 does scale and for another reason (see below). As 
for limited reach, I agree that point-to-point connections measured in the 
hundreds of meters are not adequate for a MAN / WAN. But I also don't think 
that consideration is relevant to iSCSI (from the protocol perspective), 
whose purpose is to permit a diversity of media solutions appropriate to 
each user's needs.

>Firewire also places scatter/gather on the drive together with direct access.

I think you're confusing SBP-2 (which does locate the scatter / gather 
chore in the disk drive) with IEEE 1394 (which is agnostic about such 
matters). SBP-2 cannot be "native" iSCSI any more than can FCP!

It's my understanding that the charter of iSCSI is to be transport neutral. 
That is, iSCSI is supposed to run over anything---copper, fibre, tautly 
stretched string---that supports Internet protocol. Is this belief in error?

If that assumption is correct, then when it comes time to compare and 
contrast the cost and efficiency of different media, IEEE 1394 ought to be 
in the matrix along with Ethernet, FC, UTP-5, etc., etc.


Regards,

Peter Johansson

Congruent Software, Inc.
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Berkeley, CA  94707

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