HP XP Racks - Manual (Page 444)

Description Item
Identifier of the port. Port ID
Attribute of the port indicating I/O flow. Attribute
•
Initiator: Issues I/O commands to a target port when I/O is executed
between storage systems with Continuous Access Synchronous, and so
on.
• Target: Receives I/O commands from a host.
444 LUN Manager GUI reference