Valve opens its latency-reducing, DoS Protective Network Relay infrastructure to all developers using its Steamworks platform Over the past few years, large-scale denial-of-service attacks on game servers have made the news and become a frustrating occurrence Online games and e-sports. To protect its own games, Valve has been working for several years to develop a network infrastructure that makes the system more resistant to denial-of-service attacks and lower latencies, and the company uses this system for both Dota 2 and CS: GO .
At 30 locations around the world, Valve has set up relaying servers that direct network traffic between clients and servers. These relay points provide DoS resilience in a variety of ways. They are equipped with a total bandwidth of several terabits, so that they can handle in any case, a certain flooding. Games can also switch from one relay to another without necessarily interrupting the connection. This switch can be made to another relay in the same place or even to another point of presence.
Relaying allows Valve to mask both the IP address of the game server and the IP addresses of clients connected to the server. This prevents direct attacks on another person on the same server.
The system of Valve also decides how the traffic is conducted. The company has a private backbone network with more than 2,500 ISPs around the world used for both Steam downloads and network traffic, and has prioritized network traffic over downloads. Clients can estimate the latency between two endpoints through the relays without having to send traffic between those endpoints. This allows the clients to decide which presence point to use to ensure the best ping time. According to Valve, 43% of the players were able to reduce their ping times slightly, with 1
In addition, Valve operates STUN / TURN servers, which represent a reliable method for machines behind firewalls and network address translation systems to send and receive network traffic.
This relay system is now available to all developers creating a game with the Steamworks Toolkit from Valve. The underlying network protocol without relaying has been available as open source for some time. As with many custom network protocols (such as the upcoming HTTP / 3 protocol), it relies on the simple, unreliable User Datagram Protocol (UDP) protocol, not the more complex but reliable Transmission Control Protocol (TCP) above on the UDP layer. The protocol is encrypted and performs many of the various tasks required to establish reliable transmission over UDP, so it is useful without the Steamworks forwarding capabilities.
As a fan Dota 2 I can report this network of Valve work seems to have made the work admirable. For a while, attacks were a common feature of the professional scene. Many professional games were interrupted because both players and servers were flooded with traffic. The same attacks seem to have completely disappeared.