Starbound Academy

Encryption: how secrets stay secret

Starbound Academy · Three short tiers: kids, semi-pro, elders · Pick yours

Every day we share little secrets: a note to a friend, a bank code, a family photo. Encryption is how those secrets travel safely. Jump to your part: Young Defenders · Mid group · Elders · What it costs

1. Young Defenders (ages 8–14)

The secret note

Mia passes Leo a note in class. If the teacher grabs it, Mia doesn't want it read. So they agree: every letter moves 3 steps forward in the alphabet. A becomes D, B becomes E. That's a Caesar cipher, used over 2,000 years ago. The "3" is the key. Only friends who know it can read the note.

Slide until it makes sense. Type your own note too!

Hmm: there are only 25 shifts, so anyone patient can try them all. Real encryption uses keys with so many possibilities that all the computers on Earth couldn't try them all.

The mailbox and the key

Picture a mailbox with a slot. Anyone can drop a letter in: that's your public key, and you can share it with the whole world. But only you have the little key that opens the box: your private key. Never share that one.

The padlock in the browser 🔒

See the little lock (or "https") by a website's address? It means the page and you talk in a secret code nobody in the middle can read. No lock? Never type a password there.

Passphrase power

"cat12" is short and easy to guess. "purple-tiger-eats-cold-pizza" is long, silly and easy to remember. Longer beats trickier.

Mission: write a secret note to a family member with the decoder above and see if they can crack it!

2. Mid group (semi-pro): what’s under the hood

Symmetric (AES, a NIST standard, FIPS 197): one shared key locks and unlocks. Very fast, used for the actual data. Asymmetric (RSA, ECC): a public/private key pair. Slower, so it's used to agree on keys and to sign.

Key exchange: two devices that never met agree on a fresh shared key over an open network (for example Diffie-Hellman), then switch to fast symmetric encryption.

Hashing ≠ encryption. Encryption is reversible with the key. A hash is a one-way fingerprint. Sites should store passwords as slow, salted hashes (Argon2, bcrypt, scrypt): a random salt per user means two people with the same password get different hashes, and pre-computed guess tables stop working.

What the padlock really proves: TLS means the connection is encrypted and the certificate matches the address you typed. It does not prove the site is honest. A scam site can have a padlock too. Always check the address.

End-to-end encryption in messengers: only the people in the chat hold the keys, not the service in the middle. Compare the "safety number" or security code with a friend in person once.

Post-quantum: on Aug 13, 2024 NIST published FIPS 203 (ML-KEM), a key exchange designed to resist future quantum computers (NIST, CSRC, Federal Register). Updates are rolling out quietly; keeping software updated is how you get them.

Do it today: ✅ turn on device encryption (and a screen lock) · ✅ use a password manager with a unique password per site · ✅ turn on 2FA (two-factor authentication), ideally an app or passkey · ✅ keep updates automatic.

3. For our elders

Keeping a secret is an old and honourable thing. Scripture says: "It is the glory of God to conceal a thing: but the honour of kings is to search out a matter." (Proverbs 25:2, KJV, read it)

And: "A talebearer revealeth secrets: but he that is of a faithful spirit concealeth the matter." (Proverbs 11:13, KJV, read it)

Encryption is that faithful spirit, built into your phone. It quietly keeps your letters, photos and bank visits private.

The little padlock 🔒 next to the website address means your words travel sealed, like a letter in an envelope. Before typing a card number, look for it. But remember: it shows the envelope is sealed, not that the sender is kind. Check the address too.

Never share codes. A code that comes by text is your house key. Your bank, your doctor and your grandchildren will never ask for it. Anyone who asks for it, even kindly, is not to be trusted. Say "No, thank you," and hang up.

What does encryption cost, and who pays?

Kids: almost nothing! Your phone does it in a blink, and many website padlocks are free.

Elders: you don't pay for it. It's already in your phone. Not using it can cost far more.

Semi-pro:

CostReal figure (year, sources)
Compute & batteryOn one large provider's production servers, TLS took "less than 1% of the CPU load, less than 10 KB of memory per connection and less than 2% of network overhead" (2010; ImperialViolet, repeated by istlsfastyet.com). Most phone and PC chips have hardware AES, and a lighter cipher mode exists for low-end phones without it (Android Source docs, NIST FIPS 197 for AES itself). No battery figure is quoted here; we found none we could double-source.
CertificatesLet's Encrypt gives website certificates for free and is run by the nonprofit Internet Security Research Group, a 501(c)(3) (letsencrypt.org, ISRG, ProPublica Nonprofit Explorer). Paid certificates exist too, mainly for extra identity checks and support.
Key managementThe real work is people and process: keeping keys safe, renewing, backing up, rotating. Only 37% of breached organizations said they encrypt sensitive data both at rest and in transit (2026; IBM newsroom).
Cost of not encryptingAverage data breach: USD 4.99 million, a record, up 12% (Cost of a Data Breach Report 2026, breaches Mar 2025 to Feb 2026; IBM, Help Net Security, Network World).

Who pays? Device makers build in the hardware, website owners run certificates and keys, and when it fails, the victims and the business pay for the breach.

Example only (made-up data): a family photo album of 1,000 pictures sits on an encrypted phone. The phone is lost on a bus. The finder sees a lock screen, not your photos. Cost to you: a new phone, not your privacy.

Sources

With care, the Starbound team