and UDP/IP. It was intended to be simple enough that multiplayer features can be added to a game "as little as a dozen lines of code". Grapple took care of creating, monitoring and closing connections to a server, and allowed support for multiple servers. It was message-oriented, where clients and servers each maintained a message queue, but also permitted relaying messages from client to client. There was also support for a game lobby system. The package was released under the GNU LGPL. Games using Grapple Ballistics (Linux Version) by Linux Game Publishing Candy Cruncher (Linux Version) by Linux Game Publishing Jets'n'Guns (Linux Version) by Linux Game Publishing Knights and Merchants: The Shattered Kingdom (Linux Version) by Linux Game Publishing Majesty: Gold Edition (Linux Version) by Linux Game Publishing Sacred: Gold (Linux Version) by Linux Game Publishing Applications using Grapple PenguinPlay, Multiplayer matchmaker for games. Copy protection Linux Game Publishing employs a simple form of digital rights management similar to that employed by Games for Windows – Live. Upon the first run of the game, the user is prompted for a license key, alongside their LGP user name and password. Some features include: LGP copy protection does not require internet connection to install or play the game. This system does not require user to keep the disc inside the CD drive while playing games. This system enables users to install the game on multiple systems (as there is not a limited number of activations), while also discouraging sharing by noting that any user who has access to the owner's LGP account credentials could potentially lock the owner out of their own game. Games published Currently, LGP has published nine games that contain their DRM technology: Owners of a game license can transfer the license to someone else, download a replacement disc image and allow people to see that the license is valid if they buy your game. Owners can retrieve lost keys and forgotten passwords. Buyers can check to see if they are buying a game with a valid license. Open source projects Besides Grapple, above, LGP released and contributed to several open-source projects. They created several patches for OpenPlay, that fix broken Linux support, bring some functionalities that are present in DirectPlay. They worked on other open source projects such as SDL or OpenAL. LGP worked on GPL’d the Soul Ride engine at SourceForge. Michael Simms also claimed that LGP