Where I live, a graduate with an MBBS degree (Master of Medicine, Master of Surgery) is called a doctor. To me, strictly speaking, he is a doctor only...
In computer networking, a virtual storage area network (VSAN) is a collection of ports from a set of connected Fibre Channel switches, that form a virtual fabric. Ports within a single switch can be partitioned into multiple VSANs, despite sharing hardware resources.
Then the next layer is VMkernel/VSAN which of course has its own queue and manages the IO that is pushed to the MPP aka muti-pathing layer the various devices on a host. On the next level a Disk Controller has a queue, potentially (depending on the controller used) each disk controller port has a queue.