EXFO FTB-8500 Series for FTB-500 - Manual (Page 159)

Port Tabs
Ethernet and Fibre Channel Application 145
Interface Setup (Fibre Channel)
Login
The capability to log in is available only if a successful link has been
established with Framed Layer 2.

Enable: Allows, when the Enable check box is selected, to either
generate a login process when clicking on the Login button, or to
accept a remote Login command.

Advertised BB_Credit: Advertised BB_Credit is the number of frame
buffers that a local port has available to receive frames from another
port. Advertised BB_Credit is advertised to the remote port through the
login process. Choices are from 1 to 65535. The default setting is 10.

Discovered Topology: Indicates the discovered FC topology which
can be :
Fabric: N_Ports interconnected to a Fabric switching network.
Point-to-Point: link between two N_Ports.
“ - ” : When login is disabled.

Fabric Status: Indicates the status of the Fabric switching network. The
status is not available when the topology is Point-to-Point. Possible
status are:
Logged-in: The login process has completed successfully.
Failed: The login process has not been able to complete the login
process or an error has been detected. However, traffic can still be
transmitted.
In Progress: The login process is running (not completed yet).
Logged-out: The system has not logged in yet, has received a valid
Logout command from the remote port, or the Login check box has
been cleared.