When coordinating the VM NMP and any installed 3-party MIP, what operations does the PSA perform?

When coordinating the VMware NMP and any installed third-party MPPs, the PSA performs the following tasks:
■ Loads and unloads multipathing plug-ins.
■ Hides virtual machine specifics from a particular plug-in.
■ Routes I/O requests for a specific logical device to the MPP managing that device.
■ Handles I/O queueing to the logical devices.
■ Implements logical device bandwidth sharing between virtual machines.
■ Handles I/O queueing to the physical storage HBAs.
■ Handles physical path discovery and removal.
■ Provides logical device and physical path I/O statistics.

The multipathing modules perform the following operations:
■ Manage physical path claiming and unclaiming.
■ Manage creation, registration, and deregistration of logical devices.
■ Associate physical paths with logical devices.
■ Support path failure detection and remediation.
■ Process I/O requests to logical devices:
■ Select an optimal physical path for the request.
■ Depending on a storage device, perform specific actions necessary to handle path failures and I/O command retries.
■ Support management tasks, such as reset of logical devices.