Arcade game machines rely on various networking protocols to enable multiplayer functionality, online leaderboards, and firmware updates. The most common protocols include:

1. TCP/IP (Transmission Control Protocol/Internet Protocol): Ensures reliable data transmission for critical functions like firmware updates and online score synchronization.

2. UDP (User Datagram Protocol): Preferred for real-time multiplayer gaming due to its low latency, though it sacrifices some reliability.

3. HTTP/HTTPS: Used for fetching online content, such as leaderboards or downloadable game assets.

4. Proprietary Protocols: Some arcade manufacturers develop custom protocols to optimize performance for specific hardware.

These protocols ensure seamless connectivity and enhance the gaming experience in modern arcade systems.