i have a couple questions regarding the currently defined mapping of scsi
on stp. im primarily thinking of stp running on gigabit ethernet. the
SST standard defines the error recovery mechanism to be based on the
transaction. a scsi transaction running on ethernet is likely to consist
of a decent number of data frames, maybe on the order of 50 or so. my
understanding of things is that the loss of a single data frame will
require the entire transaction to be retried. am i correct in all
this? one scenario which i would think would be fairly common is for an
initiator to make data requests of a number of targets at the same
time. if several targets respond at the same time you have a situation
where multiple flows of data are arriving at the switch and are destined
for the same port, resulting in packet loss if the switch's buffering is
not sufficient. are there reasons why this sort of thing is not likely to
occur? i am basically wondering what the reasons are for feeling that
recovery at the level of a transaction is sufficient when running on a low
level protocol such as ethernet. if it appears that i am misunderstanding
something about STP or STT, which is quite possible, please correct me.
chris
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