How to share files at a LAN party

I've been throwing LAN parties for over 15 years, and in all that time the one problem that never goes away is getting files onto everyone's machines. Someone shows up with a game nobody else has, or a mod pack, or a dumb meme they need the whole room to see, and now you have to get it from one PC to a dozen others ASAP.

What always bugged me is the default answer. In the brave new world of the cloud, the most frictionless way to move a file between two computers sitting six feet apart is to upload it to a data center a thousand miles away and then download it all the way back. It works, but I find it unsatisfying. The files are already in the room. This guide covers moving them the short way, across your own network, and the tradeoffs of every method I've tried over the years.

Ideas I've tried that weren't perfect

Whatever clever idea you're thinking of, I've tried it at some point in the last decade.

Tell everyone to pre-download the games

In theory this is the most efficient option: hand out a list ahead of time and everyone shows up ready to go. In practice, almost nobody does their homework.

Pass around USB flash drives

This works, and if you buy a stack of cheap drives you can hand out games as people arrive. But it's inelegant. You spend the morning copying data onto sticks one at a time, you've got no recourse if you fumble one, and there's no good story for the guy mid-party who wants to share something on the spot.

Cloud storage during the party

Post a link and let everyone download while they're sitting there. The catch is duplication. A 10 GB game shared with 16 people is 160 GB across your internet connection. And you're splitting one gigabit pipe 16 ways, so everyone's crawling along at ~60 Mbps. Games are big and this scales badly. There's also the bootstrapping problem of getting the link to everyone, which assumes your whole group already shares some chat app.

A little HTTP server on the LAN

Python's built-in http.server gets you 90% of the way with almost no setup. The trouble is you now have to get everyone to type an IP address into their browser. Once you get everyone going, you're still one host feeding N clients off a single connection, with no easy way for guests to share something back.

Windows file shares (SMB)

Same bottleneck as the HTTP server, plus recent versions of Windows have banned passwordless SMB shares for security reason, so now you're setting passwords or fiddling with per-account permissions. You also still have to communicate an IP or hostname.

Steam Local Network Transfers

A great feature, and I use it often, but it's one-to-one. If only one person has a game installed, the first guest to grab it pulls it locally and everyone else ends up downloading over the open internet anyway. (Side note: you can share most Steam games with LANBucket by sharing the game's folder, found under C:\Program Files (x86)\Steam\steamapps\common\.)

Dedicated LAN sharing apps

There are purpose-built tools for this, and I've run several. LocalSend is clean and cross-platform, but it sends from one device to another, so it bogs down when a whole room wants the same file. DC++ is powerful, though it expects you to set up hubs and share lists, and its dense interface scares off non-technical guests. D-LAN does the distributed transfers I wanted, but its folder-based UI never felt like the low-friction path for my crowd. Each one got me part of the way, which is what pushed me to build my own.

The fast way: distributed sharing

With the network sorted, the actual fix is simple. Almost every method above leans on a single source: one PC, one drive, or one link feeding the whole room, so the more people who want the file, the slower it gets for each of them. Distributed (peer-to-peer) transfers turn that around. At a LAN party the file is already on someone's machine, and every machine that grabs a piece starts handing that piece to others. The more people downloading, the faster it goes, the opposite of the cloud-link death spiral. D-LAN was the one tool from that list that got this right, and it is was a major inspiration for me.

This is why I built LANBucket. It finds every other copy of itself on the network automatically, transfers over a BitTorrent-style protocol tuned for a gigabit LAN rather than the open internet, compresses files on the fly, and puts it all behind a drag-and-drop UI that looks like a shared cloud folder. Some guy turns and says "hey, you've all got to see this," drags it in, and a few moments later everyone can have it downloaded. No muss, no fuss. The setup:

Step 1: Get everyone on the same network

Everything depends on the machines being on the same local network so they can talk directly. See the networking notes above: wired is best, and if you're stuck on WiFi, keep everyone on the same access point and frequency band.

Step 2: Install the same app on every machine

Pick one local-sharing tool and install it on the PCs. LocalSend is great for the occasional one-to-one or cross-platform send, DC++ and D-LAN are the old-school distributed options. LANBucket is what I use for my LAN parties because it is faster and easier to use than those other options.

Step 3: Drag, drop, download

The easy part. Drag files or folders in to share them; everyone else sees them and downloads directly, with no links to pass around. One caveat: LANBucket is Windows-only for now, and since it's peer-to-peer among the people in the room, I'd use it only with friends you trust, not a public LAN full of strangers. If you want the longer story behind all of this, I wrote up why I built LANBucket.