Dynamic Network Authentication System (DNAS) is a proprietary authentication system created by Sony Computer Entertainment Inc. DNAS retrieves information about a user's hardware and software for authentication, copy protection, account blocking, system, rules, or game management and other purposes.

DNAS consists in using a set of codes in a protected area of the game DVD together with serial numbers from the console EEPROM for online authentication. Game backups or copies using regular DVD-R burners do not have this protected area, and the games fail to authenticate to the servers. To circumvent this, programs have been made available that patch the client portion of the game to report hardcoded values without attempting to access the protected area of the DVD. This makes it possible to play online with game backups and illegal copies.

Some games have a double DNAS check to prevent people from patching them. These techniques have been introduced by Electronic Arts in most of their recent games, but it has not shown any positive results. Many new techniques for authentication are being tried, with very little success for the game companies. A group of computer hackers have found a way to bypass the DNAS server and use cheats online. This issue marks games such as Socom II and Socom Combined Assault, making normal, clean games rarer.^{[citation needed]}

[edit] References

http://www.us.playstation.com/DNAS