Networking and Online Games
Unit code: HET758
|Credit points||12.5 Credit Points|
|Duration||1 Semester or equivalent|
|Contact hours||48 Hours|
Aims and objectives
After successfully completing this unit, you should be able to:
- Place the evolution of modern multiplayer computer games into the historical context of computer and network technology evolution
- Understand IP-based networking fundamentals as they pertain to interactive, multiplayer online computer games
- Evaluate a variety of client-server and client-client communication models and explain the related performance trade-offs
- Explore the significance and difficulties of the engineering trade-offs inherent in using wide-area and local-area IP networks for multiplayer immersive environments of the First Person Shooter (FPS) genre
- Explain how the Internet's performance limitations impact on a game developer’s ability to support seamless, interactive, immersive and cheat-free experiences for their players
- Explain how the network requirements of Massively Multiplayer Online Role Playing Game (MMORPG) and Real Time Strategy (RTS) genres differ from those of FPS-style games
- Identify the role of geography, network access technologies and network load in determining the latency experienced by players
- Identify and explain techniques for measuring online game traffic, and explain the role of network traffic modelling when predicting future network-layer traffic patterns
The unit of study will review IP networking fundamentals, cover concepts of unicast UDP/IP and TCP/IP communication, and use high level examples of existing multiplayer online games to discuss ISP considerations (predicting traffic loads from gamers) and game developer considerations (e.g. lag compensation, dealing with packet loss, etc).
Since this is an emerging field, the students will make substantial use of research papers, articles and documents available over the Internet or on online libraries accessible through laboratory PCs. Lectures will utilise regular slide presentations and discussions of previously published works. History (1): early networked games (e.g. 'DOOM' broadcasting on Ethernet, Doom2 improving network utilisation, networked space warfare games of the 'turns happen every X hours', etc).
- History (2): putting 'games' into a broader context of 'immersive environments' and distributed simulation environments (e.g. US military and DARPA funded work in the 1990s.
- Network transport - how the choice of UDP versus TCP depends on game style (interactivity).
- Where does Lag and packet loss come from and why are they important? (Network congestion in ISP networks and, abstractly, in home routers).
- Importance of Lag compensation techniques across different game styles.
- Current research on traffic lag, jitter and loss sensitivity in players.
- Broadband access - how the different technologies (e.g. Cable, ADSL, wireless) affect consumer experience in online games.
- Where do players come from? Topological distributions of game players and the implications for optimal location and distribution of servers on the network.
- Traffic patterns and their impact on the underlying IP network (e.g. packet size distributions, packets per second, impact on jitter, correlation of client->server traffic, burstiness).
- Future directions (emerging technologies that may affect how ISPs offer or deploy services in support of interactive multiplayer games, IP service quality, impact of NAPT/NAT on end to end transparency and client-client communication models, relationship to peer-to-peer communications models, etc).