Category Archives: Modern Cryptography

Venona

‘Venona‘ was the code name for US decrypts made on Soviet traffic, some of which were encoded using a One Time Pad. The codename in the UK was ‘Bride’ If used correctly, a One Time Pad is unbreakable. The Soviets knew this, and used One Time Pads for much of their encryptions, for trade and [...]

This post is part of a series of 46 posts which begins with The Caesar Shift, the latest post in the series is Letter Groups.

  • Add to Delicious
  • Digg This Post
  • Stumble This Post
  • RSS Feed
Posted in Modern Cryptography | Tagged , | 2 Comments

Using Spruchnummer to crack Lorenz

Before reading further, you may like to read earlier articles on XOR and the Spruchnummer error. In sending the Lorenz cipher, one German operator used the same settings to send two identical messages, or rather, near identical messages. One began ‘Spruchnummer’ and the other began ‘Spruchnr’ and continued on. The allies realised that these two [...]

This post is part of a series of 46 posts which begins with The Caesar Shift, the latest post in the series is Letter Groups.

  • Add to Delicious
  • Digg This Post
  • Stumble This Post
  • RSS Feed
Posted in Modern Cryptography | Tagged , | 1 Comment

More fun with XOR

In order to discuss how the ‘Spruchnummer’ mistake lead the the Lorenz being broken, and why we must never reuse a one time pad key, we must first understand a little more about the nature of the XOR operation. XOR is essentially a ‘bitwise’ operation, i.e. it operates on signal bits at a time. I’ve [...]

This post is part of a series of 46 posts which begins with The Caesar Shift, the latest post in the series is Letter Groups.

  • Add to Delicious
  • Digg This Post
  • Stumble This Post
  • RSS Feed
Posted in Modern Cryptography | Tagged , | Leave a comment

A Mistake with Lorenz

This is an article which discusses the mistake made by a German operator when using the Lorenz Cipher.

This post is part of a series of 46 posts which begins with The Caesar Shift, the latest post in the series is Letter Groups.

  • Add to Delicious
  • Digg This Post
  • Stumble This Post
  • RSS Feed
Posted in Modern Cryptography | Tagged , | Leave a comment

Quantum Cryptography

There have been several news items this morning about Quantum Cryptography – I plan articles on this in the future. Japancorp reports that a quantum cryptography system has sent a key over 40km of fibre optics. This is a new record. Converge Digest confirm this story, as do Asia One in a readable article.

This post is part of a series of 46 posts which begins with The Caesar Shift, the latest post in the series is Letter Groups.

  • Add to Delicious
  • Digg This Post
  • Stumble This Post
  • RSS Feed
Posted in Modern Cryptography | Tagged , | Leave a comment
  • Categories

  • Archives

  • Recent Comments