PCSX2 Online

PCSX2 Online is a fork of open-source PlayStation 2 emulator PCSX2 with peer-to-peer netplay mode.

You can find the latest version here http://www.mediafire.com/?r3c1ejv5m85ekrv

Disclaimer

At the time, this project was conceived as a proof-of-concept and a fun challenge. I don't have as much free time now, nor do I have any incentive to go on with this project.

I wanted to play Melty Blood online, so I hacked PCSX2 just for that. Since then we've got an official PC port with much better netplay (even though I haven't been playing Melty much lately), so I can't find any reason to force myself to go on with this project.

If anyone wants to continue with this project I'm more than happy to share my knowledge.

How to start netplay

System -> Boot Netplay. The connection dialog is pretty self-explanatory.

What you should know before playing

To avoid desyncs do not change any settings except for the controller plugin configuration. It's not like it will definitely desync if you change anything, but the possibility escalates.
During netplay, emulation settings are temporarily reset to defaults with all speedhacks disabled, so performance may drop a bit. And by 'emulation settings' I mean Config->Emulation Settings dialog, so plugin settings remain intact.

Features

Peer-to-peer network connection, no centralized servers needed
Automatic input delay detection

(Official) Working games list

Melty Blood Actress Again
Tekken 5
Capcom vs SNK 2
Guilty Gear XX Accent Core
Hokuto no Ken
King of Fighters 2002 Unlimited Match
Naruto: Ultimate Ninja 3

Working with frequent desyncs

Fate/Unlimited Codes
King of Fighters XI

Changelog

2012.01.22
This build doesn't force Skip Mpeg hack to be enabled, as it's incompatible with some games.

2011.12.02
1. Some cases of emulator hanging during netplay are fixed;
2. Compatibility is improved (for example, Tekken 5 now works);
3. Crashes during netplay should be less frequent now.

2011.11.12
Desyncs should now occur much less frequently than in previous version.

2011.10.31
1. Booting from physical disc/mounted ISO works;
2. Connectivity problems fixed.
3. Netplay or replay playback can be started only after clean emulator start (as it always desyncs otherwise).

2011.10.27
1. Improved GUI;
2. Replays (Press F4 to toggle fast-forward when watching);
3. Input delay fine-tuning (Available to hosting side);
4. Option to make memory card read-only (Available to hosting side, client's MCD is always read-only);
5. Bugfixes.

2011.10.09:
1. Client side downloads memory card from hosting side to stay in sync. When the session ends, saved state persist only on hosting side;
2. Frameskipping after slowdown due to packet loss should be fixed now;
3. Some stability issues addressed.

Roadmap

Desync detection/correction;
Support more games.

BevP90/pcsx2-online