Post
Connect players directly to each other for free, or run your own servers for control -- both choices have painful tradeoffs.
Peer-to-peer (P2P) networking connects players directly to each other, while dedicated servers route all traffic through a centralized server. P2P is cheaper (no server costs), has lower latency between nearby players, and scales naturally because each player contributes bandwidth. But P2P exposes player IP addresses (enabling DDoS attacks), makes anti-cheat harder (no authoritative server), and suffers when any single player has a bad connection because they affect everyone. Dedicated servers provide authoritative state, consistent performance, better security, and fairer matches -- but cost money to run and maintain. Many games use hybrid approaches: P2P for casual modes and dedicated servers for ranked play, or P2P with host migration that transfers the hosting role if the current host disconnects.
Example
Call of Duty famously used P2P networking for years, which led to 'host advantage' where the hosting player had zero latency while everyone else lagged. The series eventually moved to dedicated servers for competitive modes after years of community complaints about unfair matches decided by who happened to be hosting.
Why it matters
The choice between P2P and dedicated servers shapes every aspect of the multiplayer experience -- fairness, latency, cost, reliability, and security. It is one of the first and most consequential architecture decisions a multiplayer game developer makes, and switching later is extremely expensive.
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