GGPO

GGPO (Good Game Peace Out) is middleware designed to help create a near-lagless online experience for various emulated arcade games and fighting games. The program was created by Tony Cannon, co-founder of fighting game community site Shoryuken and the popular Evolution Championship Series. Before its creation, GGPO creator Tony Cannon was completely dissatisfied with the 2006 Xbox 360 re-release of Street Fighter II: Hyper Fighting after experiencing its criticized online capabilities. As a reaction to its service, Cannon began development on GGPO and released the first version in late 2006. Cannon later demonstrated GGPO to Capcom, and it was positively received. The downloadable GGPO client supported many games from Capcom and SNK, including Super Street Fighter II Turbo, The King of Fighters 2002, and Metal Slug X through the use of a built-in emulator. Video game companies have also implemented a licensed version of GGPO. Games using it include Skullgirls and Street Fighter III: 3rd Strike Online Edition. On October 9, 2019, Cannon announced on his Twitter account that GGPO was now open source and available under the MIT License. GGPO uses a netcode technique called "rollback".