Client-Server Synchronization in Online Games (Part 1)

Do you use frame synchronization technology

In online game development, network message transmission inherently suffers from unstable latency fluctuations. Synchronization issues are among the biggest challenges faced by new developers entering the online gaming domain, particularly because smooth gameplay directly impacts the player’s experience.

The Importance of Frame Synchronization

In highly latency-sensitive games such as MOBAs, Frame Synchronization is a common networking model. This model ensures fairness and smooth control by maintaining absolute consistency between the client and server timelines. Achieving this goal requires optimizations on both hardware and software levels:

1. Hardware-Level Optimization:

• Deploy dedicated servers in different regions to minimize network latency.
• Leverage cloud platforms (e.g., GCP or AWS) to provide stable real-time connections using high-speed networks.
• Through these methods, physical network latency can be controlled within the 30–400ms range.

1. Software-Level Optimization:

• Frame Synchronization technology divides game time into fixed time slices, synchronizing all player commands based on these intervals.
• Considering the fastest human reaction time (approximately 150ms), we derive the following conclusions:
  1. Actions occurring within 150ms can be considered simultaneous.
  2. Latency between client and server within 150ms has minimal impact on user experience.
  3. Time slices adjusted by a speed factor of 0.85–1.15x are imperceptible to players.

Optimization Mechanisms for Frame Synchronization

Based on the above conclusions, we have designed the following optimization rules for Frame Synchronization:

1. Baseline Latency Setting:

• Before the game starts, measure network latency for all players in a room and set the highest latency as the baseline.
• If latency exceeds 150ms, cap the baseline at 150ms and align all players to this reference value.

1. Dynamic Time Adjustment:

• During gameplay, adjust time synchronization dynamically based on the time difference between client and server within a 0.85–1.15x range.
• When the time difference exceeds 150ms, the game accelerates; when it falls below 150ms, it decelerates.
• Maintain the time offset within the 100–200ms range.

1. Periodic Latency Calibration:

• Regularly monitor network latency and recalibrate the baseline value if necessary.
• Prevent incorrect initial calibration data from causing prolonged deviation, which could affect long-term gameplay stability.

Through the above mechanisms, we can effectively overcome network latency issues, ensuring a stable and smooth gaming experience globally. Developers can fine-tune these parameters based on their game type to create the most suitable solution.

As technology continues to evolve, Frame Synchronization still holds potential for further improvements, whether in reducing latency, enhancing performance, or adapting to various game scenarios. These areas remain key directions for our ongoing efforts.