Hi,

You still have to do with latency extending FC over these distances.

A dark Fibre link adds a latency of around 5 micro seconds per km. Typical SCSI transactions require a transaction to transverse the link 8 times or four round trips.

This means a dark Fibre link of 30 km adds a latency of 5 µs * 30km * 8(trips)= 1200 micro seconds(µs) = 1.2
milliseconds (ms) which is negligible for most applications, but it could affect time sensitive transactional.

From a storage point of view, only writes will transverse the Dark Fibre. If I am correct, from an IOPS perpective, only 833 IOPS remain when calculating with a latency of 1,2ms over 30KM. Is this a correct statement?

Or does the Cisco MDS series has some kind of smart technology on-board to accelerate this?