Network.InitializeServer 's IP?

In M2H’s zero to hero guide’s example1’s case,

Make simple chat script’s standalone for test, and give it to another user,(B)

and I (A) run the unity chat application and start server,

then user B also run the chat application, and what must B write down in IP and Port text field?

User A must type window Start-> cmd → type ‘ipconfig’ and know A’s own IP and inform that IP to B?

Then how about port? If A start server, how know his own port? Is it also default 25001?

Client B must enter the ip address of Server A. If they are both on the same box then it’s 127.0.0.1 which is localhost.
If they are both on the same subnet, Server A must look at his ip address that is connected to the LAN.
Client B must use that ip address to connect.
Both Server A and client B must use the same port.
if Server A has started his server on port 25000 then client B must connect to port 25000