Paper key: 4.096 bits RSA key in a Datamatrix 2D barcode

From http://www.safeberg.com. Can online backup be secure? Safeberg devised a rather large key (4096 bits RSA) that can be printed on paper. This video shows why.

Category:

Science & Technology

Tags:

• online backup
• RSA
• backup
• Safeberg
• Key
• Paper key
• security

[Talis29]

If nothing else, the nerd in me positively loves this. :)

[drtune]

When you enter alphanumeric passwords you don't use all 256 characters; most people use a-z and have to be nagged to use A-Z and 0-9.

If you use passwords only containing a-z you're only adding about 5 bits of entropy per password letter.

[jansenkarlijn85]

kaas

[tiqonijsse]

kaas

[omababy]

Neither does a piece of paper.

[prophetmk]

Anyhow, AES is the best symmetric encryption these days.

[marcan42]

There's a related-key attack on aes-192 and aes-256. Look up AES security on wikipedia. I'm not saying it's broken, just that it's had an attack published whereas AES-128 hasn't.

[wconstantine0]

hehe me 2

[RicardoPutten]

A thumb drive doesn't automatically backup your files

[omababy]

hows about a thumb drive

[DaanCeelie]

What vulnerability for 192-bit AES is that?

[bladieblaist]

@thebramp Not 4k are even less then two times secure! As RSA is 1024bits is equivalent to 80-bits of security, and 15360-Bit RSA is equivalent to 256-bits of security.

Having a big modulus ( i.e. 4096-bits) does *not* mean that this that this is real security bits. The underlying problem is Factorization, i.e. the modulus n is a product of two primes p and q. Finding the factorization n, i.e. finding p and q for n, will only take 2^80 calculations for a 1024-bits, hence the 80bits.