Networked Games - Game Programming Algorithms and Techniques - page 317

Summary
Networking is a very deep concept, and this chapter covered the important basics.
The cornerstone of any networked game is the protocols that allow transmission
of data over the network. Although TCP has guaranteed reliability, most games
choose tousethe more efficient UDP.Once the protocol isselected, the next major
decision is what type of network topology will be utilized. Although the major-
ity of real-time games today use a server/client model, most RTS games still use
peer-to-peer. The topology will greatly influence how the networked game has to
perform every update. Finally, an issue that every multiplayer game programmer
has to face at one time or another is cheaters, and there are a number of counter-
measures that can be employed to combat them.
Review Questions
1 . What is the Internet Protocol? What is the difference between IPv4 and
IPv6?
2 . What is ICMP and how might it be used for a game?
3 . What are the main characteristics of the TCP protocol?
4 . What is a port in networking?
5 . Why is the UDP protocol generally more preferable for real-time games?
6 . What is a server/client model, and how does it differ from peer-to-peer?
7 . What does client prediction entail? How does it enhance the gameplay ex-
perience for players?
8 . Briefly describe how the peer-to-peer “lockstep” model works for RTS
games.
9 . Give an example of an information cheat and how it might be combated.
10 . What is a man-in-the-middle attack, and how can it be prevented?
Additional References
Frohnmayer, Mark and Tim Gift. “The TRIBES Engine Networking Model.”
This classic paper outlines an implementation of adding reliability and data
streaming to UDP, as used in Tribes .