The MultiBindingTcpListener does not allow 0 as port parameter in the constructor. But port 0 is a valid parameter of the TcpListener class. "Specify Any for the local IP address and 0 for the local port number if you want the underlying service provider to assign those values for you. "

Scenario:
In integration tests we want to start multiple FTP servers in parallel without specifying the port number. Once the FTP server is started the assigned port is read and used in the corresponding FTP clients.