ELI5

What it is

Cipher Station lets you run your own little corner of the internet on a computer you already own. A cheap Raspberry Pi works. So does your Mac. The program you run is called a station, and it belongs to you — no company in the middle, no account to ban. Your station holds your stuff and only hands it out to people you've said yes to.

Locking things up

Before anything leaves your computer, Cipher Station scrambles it. That's encryption. Whatever carries your data around only ever sees the scrambled version. The friends you picked get a key. Without a key, you can't open it.

The locks are also built to survive future quantum computers — people call these post-quantum locks. Scrambled data copied today stays unreadable years from now.

Where the files go

Your files don't sit on one company's server. They go into a big shared storage network called IPFS. Files there are named after their own contents, and that name is called a CID. Two files that are exactly the same get the same name. Anyone who has the name can fetch the file and check that nobody tampered with it. Your files are still locked, so all this network ever holds is scrambled blobs.

Finding you

Your station has a permanent name called a Peer ID. Your home internet address can change. Your public web link can change. The Peer ID doesn't. People look it up and it tells them where you are right now. It's the phone number you keep even when you switch carriers.

Posting a photo

Here's what happens when you share a photo. Cipher Station locks it, uploads it to IPFS, and gets a CID back. Then it makes a key for each friend you chose. It updates your list of posts, which is called the manifest, and re-points your permanent name at the new version. Your friends look up your name, grab the photo, use their key, and see it. Everyone else just gets a scrambled mess they can't read.

Who can see each post

You decide this every time you post:

• Just you.
• A few specific friends.
• All the followers you've approved.
• Public, which means anyone can read it, no key needed.

Be careful with public posts. IPFS has no delete button, so only make something public if you're fine with it being out there forever.

Following you isn't automatic either. When someone asks to follow you, the request just waits until you say yes.

One more thing

Cipher Station is a set of rules, not a single app — a protocol. Anyone can build their own app on top of it; one that already exists is CipherVault, a bit like Google Drive except it runs on your own station instead of someone else's cloud.

Want the real mechanics? Head to Fundamentals. The code itself lives at github.com/CharliePetch/cipher-station.