Welcome to the second part of our special feature on setting up a world class LAN Party. In Part 1, I described how to organize a smooth-running LAN party and get it powered properly. In this article, I will focus on the LAN Party's network infrastructure.
We all know that attendees come to LAN Parties for the fastest ping times possible and smoothest game play. In this installment, I'll be describing the how-to's of selecting and setting up the LAN's switching gear and provide some cabling tips to ensure that everything produces the desired state of gaming LAN bliss!
The Pulse of the Network
When setting up a network, you need to understand the kinds of traffic it will be handling and their flow. Someone who is familiar only with corporate networks can be at a disadvantage when setting up a LAN Party network. Because while the equipment itself is the same, the data traffic and flow can be quite different.
Both corporate and LAN Party networks use TCP/IP as the primary protocol. Some very old games still use IPX/SPX, but all major games currently played at LAN Parties work over IP using UDP (User Datagram Protocol).
UDP was designed to handle packet loss more effectively than TCP over low-quality connections (like the Internet). With TCP, a single dropped packet could cause a significant delay as the protocol attempts to locate and/or resend the lost packet. UDP does not recover lost packets, but simply ignores them and continues to allow the application itself to compensate for this lost information.
Lost packet compensation is done by programmed algorithms that estimate or "predict" movements of other players and objects within the game world. By using this technique, games are playable on the Internet where packet loss is prevalent. Interestingly enough, even if your LAN network isn't set up properly, games should still work and will compensate the same way they do if you are on the Internet, but the glitches will be more dramatically noticeable on a LAN for some older games that don't allow you to tweak settings for LAN vs. Internet speeds.
Another type of traffic that is found on a LAN Party network is known as a broadcast - a type of packet that is not sent just from one computer to another, but instead from one computer to every computer on the network. Broadcasts are very important to a LAN Party network, but can affect performance dramatically as the number of machines on the LAN increases.
Another big difference between corporate and LAN Party networks is in the traffic patterns. A LAN Party usually has a number of players connected to a game server, which is not always placed on a super-fast link connected to the root of your network. Many times, a player connected to a floor switch will start a server from his own PC right on the floor. This dramatically increases the importance of connectivity from the floor switches to be very fast and reliable because packet loss occurs when uplinks are saturated. I'll discuss this further in the LAN Topology section.
Additionally, centralized services such as DHCP and DNS services may not be available on a typical LAN Party network. However with some simple instructions in our next article, we will show you how to set up some of these services to reduce the burden of broadcasts on your network.
Finally, you will find all kinds of file sharing and random activities on a LAN Party network that require connections all over the place. In a business, users are usually primarily connecting to central servers or gateways connected to the core switch. In a LAN Party, one PC is just as likely to be talking to another PC as to a server!