Design flaw in the SCSI spec?

Eric Smith spacewar at
Wed Jan 8 18:04:34 CST 2020

On Wed, Jan 8, 2020 at 4:57 PM Bill Gunshannon via cctalk <
cctalk at> wrote:

> And then you have DEC.  I have often heard DSSI described as
> SCSI done right

That's reportedly what DEC thought of it, but in practice it was SCSI done
differently so as to be incompatible. The only technical "advantage" of
DSSI was that it better matched some of DEC's other proprietary storage
standards, thus enhancing vendor lock-in and profitability.

If you were another company trying to decide whether to use SCSI or DSSI in
your products, even if licensing and related cost weren't at issue, the
_only_ reason to use DSSI would be to interoperate with DEC.

I was a fan of DEC, but they did plenty of things for vendor lock-in rather
than technical reasons.

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