MultiPad Cipher

This form will take whatever string of text you give it (up to about 1000 characters), encrypt it using a MultiPad Cipher (see below), and then generate QR codes that can be scanned with a mobile phone. You can determine the number of pads to generate by using the pulldown menu.

What is a MultiPad Cipher?

Building upon the concept of a One-time Pad or Vernam Cipher, this MultiPad Cipher (or MPC) encodes a secret message in an arbitrary number of noise layers (one-time pads). In this way, the MultiPad Cipher is uncrackable unless each and every layer is combined, since each layer is effectively random noise.

Presently there are three modes here:

When each QR code is scanned it contains a link back to this page which will then keep a tally of each pad entered and output their current combination. Once all codes are scanned, the message will be revealed!

You can also theoretically encode a number of decoy messages into the pad tally which reveal themselves when different combinations of pads are entered, thus leading a snoop with only some of the pads off the trail. Since this is simply a proof-of-concept, I haven't implemented that functionality yet, and there will be bugs! So please be patient and be sure to test your codes before using them for anything.

What Are Some Practical Applications?

Where a standard One-Time Pad has many applications, say you have the combination to the family safe or a list of account numbers that you wish to bequeath to a specific group of family members. One could encode such information with a MultiPad Cipher, give one pad to each family member, and keep one with your lawyer. This way, all relevant parties have a piece of the message and yet none have means of deciphering it or altering it until they all are present and work together.

Another more whimsical application would be a digital scavenger hunt such as Geocaching where a prize or message is revealed by collecting all of the appropriate QR codes.

In essence, a MultiPad is a high tech, secure version of divvying up a treasure map.

Important Notice:

I cannot guarantee any security on this website
(note that this is not https),
so please don't do anything silly with this.

Notes & Props:

The MultiPad Cipher is © 2014 me, Steve Caruso.

Its implementation makes use of the phpqrcode library by Alexandre Assouad and Dominik Dzienia which in turn is:

Based on C libqrencode library (ver. 3.1.1)
Copyright (C) 2006-2010 by Kentaro Fukuchi

QR Code is registered trademarks of DENSO WAVE INCORPORATED in JAPAN and other countries.

Reed-Solomon code encoder is written by Phil Karn, KA9Q.
Copyright (C) 2002, 2003, 2004, 2006 Phil Karn, KA9Q

Version History: