EXFO FTB-8500 Series for FTB-500 - Manual (Page 366)

TCP Throughput Tabs
352 FTB-8500 Series and FTB-8120NGE/8130NGE
TCP Throughput Configuration
Press TEST, TCP Throughput, and TCP Throughput Configuration.
TCP Mode
Since two units are required to perform a TCP Throughput test, one unit
must be the source (Local) unit and the other one the destination
(Remote). Set the TCP Mode on both units. Choices are Local and Remote.
The default setting is Local.
TCP Connection Configuration

Remote IP Address (Available with Local TCP Mode): On the local
unit, enter the IP Address of the remote unit.

Listening IP Address (Available with Remote TCP Mode): On the
remote unit, enter the IP Address of the local unit. The IP address
0.0.0.0 can be used to listen to any TCP stream. The default setting is
0.0.0.0.