User`s guide

230 Implementing an Open IBM SAN
Usage of public loop and private loop
Since these two loop modes inherit different protocol methods, there are
differences in the actual usage of them with the INRANGE IN-VSN tool.
Usage of public loop
You can attach public loop initiators or targets without any additional settings,
provided that the director port is set to enable AL.
However, attaching a public loop port does not automatically mean that this port
can talk to any other ports in the fabric. This port will be recognized as an
NL_Port and can be zoned in the same way as normal N_Ports can be zoned.
An example of the recognition of a public loop port as an NL_Port in the Name
Service Table of a director is shown in Figure 3-48.
Figure 3-48 IN-VSN: Name server table with NL_Port