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, but could be a hostname), 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 220.127.116.11:5201.
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 18.104.22.168:5201
for the regular client; for the DM client, the command line might be
nwmain.exe -dmc +connect 22.214.171.124:5201
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)