Questions about a LAN party network

[Ver17]

I am organizing a LAN party and have some questions about the network configuration (throughput, vlans, switches). I have been somewhat a network guy for a while and have worked with some Cisco equipment before so I might have some foundation to start.... I just need to fill in some missing information to do this right I think.

- The LAN will be for 96 to 128 players
- We will have around 16 servers or maybe a couple more
- We are going to have multiple 24Port switches connect to a main “beefy” switch


Here are the questions that have been tumbling around in my head lately:

1. If there are 128 players using 100Mbps connections does that mean that the main switches backplane needs to handle over 12Gbps? I understand that the games cfg's will be default set to lower bandwidth settings, but I was wondering for a worst case scenario if most of the players change their configs to use the most bandwidth possible.

2. Is using fiber uplinks to connect the smaller switches to the larger switch better than 100Mb Ethernet? FX FDDI fibber is still only 100Mbps right? I only ask because fiber switch modules seem to be cheaper on eBay than Gb Ethernet modules.

3. Should I have a router in the network and sub-divide it into vlans to block un-needed network chatter? Is this really necessary?


Thanks for any info or feedback

[YeOldeStonecat]

The LAN parties we've done around 100 peeps...we used 3x Cisco Catalyst switches for our backbone.

Central switch has the servers fed to it, as well as about 1/4 of the crowd (or a little bit more).

Fiber-giga uplinks from the central Cisco to 2x more Catalysts...each located in opposite diagonal corners of the convention room we rented. Each of those split up the remaining crowd.

Didn't bother with VLans at this size. One of the gaming servers was running DHCP for the LAN. In the "posted rules of the LAN" put on the forums, and lanparty.com ad we ran, we encouraged people to pre-configure their network settings before arriving. No NetBEUI, no IPX, and TCP set to obtain auto. NIC and TCP stack in good functional order. If you're been to LAN parties in the past, you know the guys who have IT knowledge always get stuck fixing some persons junker computer trying to get their cheap 19 dollar NIC running right. I'd rather be playing!

Computers encouraged to be virus/worm free. Network shares discouraged (I've seen too many peoples computers get hosed by pranksters at LAN parties due to having wide open shares on their C$. )

Try to avoid using home made patch cables. There is always someone who insists they know how to make cables, they whip up a couple of long runs to uplink switches 'n stuff, and you spend hours trying to figure out where all the packet loss is coming from on a certain switch. Save yourself the hassle and wasted time, purchase good cables ahead of time, or get some made up and FULLY TESTED with a quality Fluke test or something good like that ahead of time. Don't waste time with some 19 dollar "link light" tester, a link light test means jack squat when it comes to performance.

You'll want the servers running a real server OS, not a desktop operating system. Desktop OSs are optimized for up to 10 concurrent connections, after that, they start to loose efficiency. Same goes for the hardware, especially the NIC. There's a big difference between a desktop NIC, and a true server grade NIC, when it comes to performance with many concurrent connections. Trust me...you can take 2x identicle computers as far as CPU, mobo, and RAM. Install a desktop OS and desktop NIC on one of them, install a true server OS and true server grade NIC on the other. Have 75 peeps connect to each playing the same game. You'll see a difference in performance.

www.blackviper.com is a good source for "tweaking and leaning out" your servers. Getting them to run lean and mean.

Make sure your servers are windows updated, and have a quality, low system impact antivirus running on them. (NOD32 *free 30 day trial*, AVG *free edition*, Symantec Corporate Edition*must have licenses*) Because surer than sh|t there will be some infected computers brought to the LAN, you don't need your server going belly up a few hours into the gaming because it wasn't protected correctly.

Check power requirements ahead of time. As our LAN parties grew, we blew a few circuits from time to time. Have your servers and switches on APCC battey backups. Spread the load well in the room. Even our more recent one at a convention room at a brand new Marriot, we dropped the circuits a few times....maintenance ran extension cords into the room, going out down the hall, to help split up the load.

Encourage headphones. Nothing worse than a few people who insist on showing off the wattage of their Klippies or Logitechs at a LAN party.

[YeOldeStonecat]

Edit, some more thoughts.
No hubs, anywhere.
Think carefully, and guard, your cable layout. Always some joker who can't pay attention, comes stumbling across the room carrying his huge monitor, oblivious to where they're walking...and his foot takes a half dozen cables with him, patch, AC, or steps on the fiber.
You mentioned backplane speeds. Well, gaming is lots of little packets, you need speed here, not necessarily high bandwidth. A 100 meg LAN will have more than enough bandwidth. With quality switch brands, along with the higher backplane speeds, you'll have the speed. But it's the speed that counts here. No 19 dollar switches in the center, you want good gear.

Focus on a star topology when connecting your switches. You want to avoid uplinking other switches into switches which themselves are uplinked to the central switch. All switches should be uplinked solely to the central switch. A little 5 port switch to get 3x more people onto a corner...sure, no big deal. But larger switches, try to have them uplinked to the central switch as best you can.

[Ver17]

Great feedback! Thanks a ton! I feel pritty well prepared and your posts will make me go back and just check a few things. The one thing that I did miss completely was the anti-virus software on the servers themselves.... good call

What kind of Cisco Catalyst switches did/do you use? (I'm just trying to get an idea on how beefy a network I am looking at needing)

You mention "Fiber-giga uplinks" on your Cisco switches.... The Cisco modules I am looking at say they are all "100BaseFX MMF Fast EtherChannel" but the "100Base" makes me think they are all mega and not giga. Am I reading this wrong? Is 100BaseFX fiber really running at giga speeds? I don't know much about fiber and I can't really find any Cisco giga fiber modules or ports for the 2900, 3500 or even the 5500 switches.... unless I am missing something thats right in front of me....

Thanks again! Great feedback and good ideas!!!

[YeOldeStonecat]

If it says 100fx, then it's 100base. Not really a show stopper IMO, shouldn't even be much of an impact on your performance. Remember, you're not moving HUGE quantities of data all at once, you're moving lots of little packets at fast rate. Latency in your concern. Wether it's 10 base, or 100 base, or 1000 base...those don't really affect latency.

We were lucky, the group that I used to setup LAN parties with, one of the guys was a main IT guy at a large insurance company, and he had permission to "borrow" some equipment for the weekends of the LAN. Se we were lucky. Going back quite a few years, he's show up with these awesome BayStack switches. The more recent years, esp that big one we did at at Marriot, he surprised us with the Cisco gear, complete with fiber runs. Those ran great. What models he had....I cannot remember. I want to say 3500 or 3550...but I can't remember. I have some pics somewhere...of when we were setting up, but I think they're home. I just dug around my computer here at work and couldn't find them.

Having the Catalysts there...you'll see all set.

[Ver17]

Coooool......

I was planning on using either Netgear or Cisco 24Port switches (depending on eBay prices and what uplink form I am going to use) with specific uplink ports for the player connections. I have a loaded Cisco Catalyst 5505 that has 72Ports of 100BaseTX and 12Port 100BaseFX MMF Etherchannel fiber connections. I would have preferred to use 1000BaseTX and not have to mess with fiber but it seems the 5500 Catalyst does not have gigabit modules so I have to decide between using 100BaseFX fiber or normal 100BaseTX Ethernet connections.... still not sure yet..... hmmmm..... this is a hard one. Unless the fiber gives me some distinct advantage I will probably use the normal 100BaseTX RJ-45 connections.


Thanks again for the feedback

[YeOldeStonecat]

still not sure yet..... hmmmm..... this is a hard one. Unless the fiber gives me some distinct advantage I will probably use the normal 100BaseTX RJ-45 connections.

Trust me, there are many other things that will have a larger impact on how well a LAN party fairs. Try to focus on eliminating the time consuming ones...so you can sit back, enjoy the LAN, and watch others enjoy the LAN.

Distribution of power
Stable servers
Ability to manage the servers quickly (have a laptop with you to admin them quickly)
Getting people setup and all playing "by a certain time" <==hard one
Organized food/drink breaks