2.1. Functional Levels
Fibre Channel Protocol (FCP) functional levels are FC-0 through FC-4. The FC-3 and FC-4 levels are outside the port level, permitting the sharing of resources of several ports in the event of future extensions. Applications lie above the FC-4 level. For example, the peripheral drivers for a SCSI application that typically communicates with Host Bus Adapters (HBAs) will communicate with the FC-4 level.
2.1.1. Placement in a Topology
As shown in Figure 2-1, FC-0, FC- , and FC-2 are implemented at the port level. FC-3, FC-4, and the Upper Level Protocols (ULPs) are implemented at the node level. Fibre Channel considers that which is not visible on the link (above the FC-0 physical level) to be system dependent, and simply ...