How DDoS Protection for Game Servers Actually Works

"DDoS protected" appears on every hosting page and means very little on its own. It is worth understanding what is actually being filtered, because the differences decide whether your server survives an attack.

Volumetric attacks: the bandwidth problem

The simplest attack floods your connection with more traffic than it can carry. Nothing running on your server can help — the traffic is already saturating the link before it arrives.

The only real defence is capacity plus filtering upstream, at the network edge, before traffic reaches your machine. This is why protection is a property of the network your server sits on, not software you install.

Why UDP is the hard part

Most game servers use UDP, and UDP is connectionless. There is no handshake, so:

• Source addresses are trivially forged.
• The filter cannot separate "real player" from "attacker" by connection state, because there is no connection state.

TCP protection can lean on handshake validation. UDP protection has to work from traffic patterns — rate, packet size distribution, whether the payload looks like the game's protocol at all. This is why a filter tuned for web traffic does poorly on game traffic, and why game-specific filtering exists as a separate thing.

Application-layer attacks

The harder case is traffic that is technically valid. Repeated legitimate-looking queries, or connection attempts that are indistinguishable from real ones, do not stand out to a volumetric filter. Defending against these means rate limiting per source and, sometimes, accepting that some real players get caught too.

Nobody can promise zero downtime

If a host guarantees you will never notice an attack, they are overselling. Filtering is a trade-off in three directions:

• Too aggressive and you drop real players — a false positive during a raid is worse than a brief hitch.
• Too permissive and attack traffic reaches the server.
• Detection takes time. There is a window between an attack starting and mitigation engaging. Honest hosts quote that window; they do not claim it is zero.

Questions worth asking

1. Is it always on, or triggered? Triggered mitigation means the first seconds always get through.
2. Is UDP filtered specifically, or just TCP? For a game server, TCP-only protection is close to useless.
3. What happens to your IP during an attack? Some providers null-route the target — which stops the attack by taking you offline. That is the outcome you were trying to avoid.

That last one matters most. Ask it directly, and be wary of a vague answer.