RE: Storage over Ethernet/IP

[Bernard Aboba]

I too have heard these arguments. When I heard them I felt a sense of deja vu -- anyone remember when the conventional wisdom was that "voice will never run over IP?" In fact, most of the assertions below are fallacies or soon will become fallacies. The only real argument is about the exact form the technology will take -- NAS vs. SAN, etc.    > a.  TCP is too CPU intensive and creates too much latency for storage I/O operations.    There are now task specific processors and co-processors that can handle 1 Gbps line rate today, and will run at 10 Gbps line rate in 18-24 months. So this argument has already fallen by the wayside.    >b.  The IP stack is too top heavy and processing packet headers is too slow to support storage I/O operations.    Too slow? If that were true, we wouldn't be able to handle OC-192, would we? The real question is how much the chips, switch fabric and specialized memory will cost, and how competitive this will be with existing technologies such as Fibre Channel, both for short and long haul.   >c.  The maximum throughput of a GE TCP/IP connection is 768 Mps, which is too slow to support storage I/O operations.    That figure was achieved with minimal hardware acceleration. Pushing it by an order of magnitude within 24 months is not unimaginable. If you were willing to throw more hardware at the problem, it might be possible to handle a 1 Gbps bit rate on 8 lambdas at the same time *today*. How does 8 Gbps of throughput today sound, with 80 Gbps in 18-24 months?    > Is any of this true?    No.