Directly connecting is the only way to join an internet server, now that GameSpy no longer hosts a list of servers. It requires knowing the IP address of the server (typically in the form of four numbers separated by periods), and possibly the port used by the server (joined to the IP address with a colon). For example, the IP address of a server might look like 18.104.22.168:5201.
To directly connect to a server from within the game, one must start a multiplayer session ("Multiplayer" off the main menu), navigate to the server list ("Join LAN Game" or "Join Internet Game"), then click the "Direct Connect" button. This brings up a window into which the IP address of the server can be entered.
To directly connect to a server with a desktop shortcut (or via a command prompt), the command line of the shortcut needs to have the parameter "+connect" added, followed by the IP address and port of the server. For example, the command line might be
nwmain.exe +connect 22.214.171.124:5201
for the regular client; for the DM client, the command line might be
nwmain.exe -dmc +connect 126.96.36.199:5201
If a password is required for the server (as is usually the case with the DM client), it can be specified on the command line with the parameter "+password" followed by the password.
- How to direct connect by IP address (BioWare website)