Multiplayer refers to games against other humans, in contrast to single player. It is still possible to add AI opponents if desired.
One player is the host of the game and others join. The methods of hosting are below.
How Multiplayer WorksEdit
Both Supreme Commander FA and Vanilla use a peer-to-peer client, this means that each computer that joins a game runs its own calculation of everything going on in a game (referred to as synchronized simulation) and the connection between computers is only utilized to send synchronization tables (that allow each pc to be in sync with each other) and player commands. Because of this there is also no such thing as a dedicated Supreme Commander server.
In the lobby for a Supreme Commander multiplayer game you may notice a ping meter. Supreme Commander can run perfectly fine with a ping as high as 500ms and is in fact designed to do so. The person with a ping of 500ms causes no more lag than a person with a ping of 2ms (meaning that you don't have to kick people with red pings or from the other side of the world as laggers if they have a ping below 500ms).
What lag is usually caused by is a lack of upload or download bandwidth, due to SupCom's peer-to-peer set up upload bandwidth is particularly critical, however as long as you are not downloading or uploading massive files you should have enough bandwidth. For a more technical explanation read this FAF forum post by uberge3k .
For Vanilla Supreme CommanderEdit
It is possible to host a game in Supreme Commander if you know the IP address of the host. If the host is on the LAN (houshold, office, internet café) you can find it within the game.
The Steam version of Vanilla Supreme Commander does not offer any multiplayer options besides LAN/IP and with the shutdown of GPG Net the box edition also lost its dedicated multiplayer service. However, Evolvehq.com offers multiplayer game hosting though the multiplayer scene seems inactive and it's unknown if this works with the Steam version. As of October the 2nd Evolve had less than a dozen on with no connection options that worked for Supreme Commander. Furthermore, asking the moderator on duty did not even get a response.
For Supreme Commander Forged AllianceEdit
It is possible to host a game in Supreme Commander Forged Alliance if you know the IP address of the host. If the host is on the LAN (houshold, office, internet café) you can find it within the game.
The Steam version of Supreme Commander FA use a seperate Steam hosting system. A helpful tip for those who still have their Supreme Commander keys is that if you use them to obtain the game on Steam it will work. Steam will utilize multiplayer with 3603 game patch gameplay.
Due to GPG net's state of decay and eventual future shutdown members of the Supreme Commander community put together Forged Alliance Forever (FAF). The goal of this multiplayer server is to allow Supreme Commander: Forged Alliance multiplayer games to be played in the aftermath of GPG Net's shutdown. FAF's website is www.faforever.com.
Forged Alliance Forever offers a multiplayer ladder, competitive tournaments, a map vault, a replay vault and integrated mods. Those mods include: LAB wars, Nomads, Blackops, FAF (the basic game which has some bug fixes and Sorian AI), Murder Party, Nuke For The Win, Wyvern Battlepack, X'treme Wars, and other mods. Mods can be turned on and off by selecting them in the FAF menu. It should also be noted that most FAF games are played with the FAF patch made by the core community which has made several slight, but noticeable changes.
GPG Net has been permanently shut down and is no longer an option for multiplayer. This section is preserved as a sort of historical memorial for it.
Finding a person hosting can be managed by the GPGNet program included with Supreme Commander and FA. Games managed by GPGNet include custom and ranked games. Ranked games affect a player's rating, to help match players of relatively equal skill. It should be noted that Gas Powered Games published an official multiplayer FAQ.