Working undercover demands the utmost secrecy. Even today, the members of Bocathur use encrypted data connections for communication. In the olden days, the Fraternity used a code which was based on the Alberti Cipher and which the members used to communicate with one another.
The Alberti Cipher is based on the principle that each letter of the alphabet correlates with a letter of a “secret alphabet”. The easiest way to do this is with the help of cipher discs. Originally, each of these discs consisted of two revolving rings, each marked with the letters of the alphabet. In order to decipher a code word, one just had to know the correlation of the letter – for example A = F. By turning the discs into this position the remaining letters and so the entire word could be decoded.
For reasons of security and distinctiveness Bocathur broadened this principle. To each of the discs there was a third ring – the smallest. This one contained a four-digit sequence of numbers, which only made sense to the initiated: the two pairs of digits each represented a position of the alphabet. 08-06 became H-F. Only those who had reached this level and possessed all parts of the disc were able to decipher the code. The sequence of numbers has allegedly been constantly changed in order to protect the Fraternity. Particularly high-ranking members are believed to have used their own deciphering key, which was known only by a few members of the Fraternity.According to tradition, each of these discs consisted of three parts. But the three parts were not allowed to be kept in the same place. Over the years, many of them have been destroyed – but rumour has it that some of them are still hidden away somewhere.