Earlier this year, fans of one of PlayStation Vita’s few first party exclusives, “Killzone: Mercenary,” suddenly found themselves unable to connect to multiplayer. The game came out in late 2013, and the Vita itself is older still; production on new units had concluded in 2019. Players feared that Sony had shut down the game’s multiplayer functionality — permanently.

It wasn’t hard to understand why players reached this conclusion. Although “Mercenary’s” servers eventually came back online (the reason for the shutdown is still unknown) Sony has earned a reputation over the past several years for unceremoniously shutting down multiplayer service for its first party franchises. In October, Sony announced that it was updating the PlayStation Network webstore to only feature PlayStation 5 and PlayStation 4 titles for purchase, effectively locking away PS3, PS Vita, and PSP games in their respective machines.

If you’re interested in the history of games, or just want to relive the good old days and enjoy some games that aren’t available on modern consoles, it’s important to have all aspects of a game preserved, and not just the offline parts. That’s where PS Online Network Emulated, or PSONE, comes in.

PSONE is a platform that uses the player’s PS3 to attempt to bring back the online functionality of certain PS3 and PS2 titles. PSONE’s developers reverse engineer the protocol used by the games to communicate with their game servers, and once the group gets a basic grasp of how it works, they implement a proof of concept server that players engage with and connect the game to it.

The project wasn’t always a unified effort, more PSMANY than PSONE, with a number of different developers chasing similar goals in parallel. One of the developers, Dominik Thalhammer, was working on restoring the servers for “Warhawk,” a multiplayer-only aerial warfare game for the PS3. Thalhammer noticed that the ways that the server and the game communicated were similar to games being worked on by other restoration hobbyists, ranging from the 3-D social gaming platform PlayStation Home to the Slant Six Games tactical shooter for PS3, “SOCOM: Confrontation.”

To avoid duplication, Thalhammer created a private Discord server and sent invites to those working on these restoration projects. “The hope was to share information and implementations, as well as a general place to discuss stuff that should not hit the general public for various reasons,” he said. If in-depth information about reversed protocols were made public, for example, it might enable bad actors to break encrypted communications and gain access to user information.

According to the common understanding of Digital Millennium Copyright Act, PSONE is legal so long as the project doesn’t receive any financial reward from preserving a game’s multiplayer mode. Though this law is specific to the United States, most developed countries have similar ones. To avoid any trouble with Sony, PSONE has a statement on its website: The project never has and never will accept donations. PSONE is free, and everyone who contributes work does so in their free time, usually ranging between 5-10 hours per week.

“Another important point is that we do not support piracy in any way. If people want to play, they should buy the game. If they do not and have problems with it, we won’t help them,” said Thalhammer.

The actual number of people who play through PSONE’s servers is small: About 20 to 50 play on a regular basis, and just over 850 players total since the project launched in August. However, both numbers are increasing; about 61 new players have started in the last seven days alone.

Trying to gather more players is an uphill battle. There are no official websites or forums dedicated to games like “Warhawk” anymore to spread awareness of PSONE on, except for general gaming enthusiast sites. Before his “Warhawk” Reborn project was put under the PSONE banner, Thalhammer had a mobile application for it; when PSONE officially started, he placed a notice about it on the application so users would know about the project. He believes he’s done the best he could to get the word out.

“There is a core of about 15 players, which will probably continue playing this game until all PlayStation 3s on the planet are broken,” said Thalhammer.

Right now, “Warhawk” and “Twisted Metal Black: Online” are the only titles that are fully functional through PSONE, though the team is hard at work restoring others. Deciding what games to work on is relatively simple: After the initial projects are done, the PSONE team conducts a simple poll in its Discord server to see which of Sony’s PS3 first party games are the most requested. PSONE focuses on Sony first party titles because they all use basically the same network code. “We are focusing on those because the ‘effort spent versus games back online’ metric is way better if you focus on one platform and do that one well,” said Thalhammer. “The fact that they are all kind of similar results in a lot of transferrable knowledge between games, which in turn reduces the work needed to bring them back online.”

The main culprit in slowing down progress is whether packet captures are readily available. Packet captures are data sent and requested in a sort of question and answer format between the game and server. For example, an initial connect request may just be the game checking to see if the server is online (the question) and then the PSONE server will reproduce the server’s response to that question (the answer). In other scenarios, the game may be sending data as varied as a kill/death ratio, or information around the creation and management of an in-game clan. To get a game to work, the team needs to emulate a proper response to the game’s “questions” to the server; packet captures can aid in reverse engineering how the game and server communicate. Generally, roadblocks come up when data doesn’t match up with what the game expects. Sometimes, those discrepancies come down to a single byte.

Packet captures for each game need to be caught through third party software — and before Sony’s official servers are shut down. For some titles, capture packets aren’t easily accessible because no one had the foresight to record them before the game’s servers were shuttered. Some packet captures have only been recovered by accident.

Aziz Alsaeed, another developer on the project, lamented Sony not taking more steps to maintain its network for the sake of game history and preservation. “PSONE always plans to be a project that aims for game preservation and archiving what we can,” he said. Eventually, support for PS3 through PlayStation Network will be cut off, and initiatives such as PSONE will take steps to archive what is needed to keep playing people’s favorite games.

Alsaeed also said that the value of PSONE is a place where players can play old online games that have been shut down, as well a way to show future generations what made those online games special. “I have a strong belief that preserving those online games will give instructors a chance to show live demonstrations. Instructors could show students how things started and shaped toward what we have now when it comes to game development,” he said.

However, Thalhammer offered a different point of view. For starters, PS3 games are notoriously hard to work with, given the console’s unique hardware design. Moreover, Sony running a server as a company is different from PSONE running a server as a free service. Sony has to consider factors such as assuring server maintenance and having customer support.

“No one can expect a company to run servers for something that does not generate any noticeable income anymore until all eternity,” he said.

George Yang is a freelance writer covering video games and culture. His work has appeared in Polygon, USGamer, The Hollywood Reporter, and more. You can follow him on Twitter @yinyangfooey.

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