Tag Archives: cryptography

What ever happened to autostereograms?

I recall the craze in the 1990s for Magic Eye posters and books. People would gaze and squint at these multicoloured, seemingly random, patterns to discern 3d images of dolphins, elephants, temples, and spaceships. The method of display was a variation on what I experienced as a child, as I gazed at my bedroom wallpaper…More

Key exchange: It’s a wrap!

In an earlier post (Elliptic trapdoors) I did my best to explain addition and multiplication along an elliptic curve. The diagram showed a point P doubled to produce 2P, then added to itself to produce 3P, and added again to produce 4P. The dotted lines indicated the mirror reflection operation to arrive at the final…More

Elliptic trapdoors

Elliptic curves are amongst a family of curves that make up the alluring surfaces of much contemporary organically-inspired architecture. They are also the basis of encryption methods that secure digital communications. A trapdoor is a one-way portal. You can go through it easily in one direction, but it’s difficult to come out again in the…More

RSA public key encryption

I’m continuing this dive into public-private key encryption. As outlined in a helpful blog post by Nick Sullivan, the kind of encryption I described in the last two posts relies on a simple property of numbers. It’s easy to multiply two numbers, even if very large, but more difficult to factor a number, i.e. find…More

Asymmetric key encryption

An encryption key is a string of characters that you feed into an encryption algorithm to either encrypt or decrypt a message. An asymmetric key system has two keys. There’s a public key to encrypt a message. It’s public because anyone can see it and use that key. But once the message is encrypted using…More

Primes

Some secure encryption methods make use of prime numbers. I’ll examine the method in the next post, but here’s some properties of primes relevant to encryption, presented via simple grid geometry. Hopefully that connects this esoteric field with spatial shapes such as rectangular rooms on a gridded plan. Composites A composite number is a positive…More

Shibboleth

A Shibboleth is a kind of pronunciation test. You can tell where someone is from, or not from, by asking them to say a particular word. It can also indicate where someone has been. I can tell with a degree of certainty if someone has been to Australia by the way they say “Melbourne.” If…More

Cryptography for space aliens

“Anticryptography” is a loose term to designate a type of cryptographic message that is legible to someone who has no knowledge of the plain text language from which the message derives. Nor do they have access to the method of encryption, or anything like an encryption or decryption key. Nor is the message meant to…More

Quantum Internet

Quantum computers can potentially remove the need to iterate through the huge numbers of combinations required to crack a code, reconstruct an original source document from a hash string or derive the key used to encrypt a file.More

How architecture keeps its secrets

Here’s a basic application of the containment principle. If you put something into a cardboard box and close the lid then it’s concealed from view. Buildings also conceal things. I discussed the house-museum of the architect John Soane in a previous post. Soane was a practitioner within a secret society (Freemasonry), which in turn traded in…More