Quote:
calling back to the initiating device


This gets used quite a bit actually in newer devices. For example, a disk with a good chunk of cache can get the data from the initiator that need to be written to the disk, then stop it's connection on the bus opening it back up. Then, once it flushes the cache out to the disk, it will call back to the initiator and say it is complete, allowing more data to be sent.

Quite a few interesting features of SCSI did get moved into Fibre Channel as well, allowing a tape library to back up a disk array without talking to a server. Ironically, instead of IP over SCSI though, things are moving towards SCSI over IP on fibre lines, to help integrate and simplify high speed data and TCP/IP networks.