Programming Gasket Grille Cypher

A programming gasket grille cypher is a form of steganography wherein one uses a carefully punched dieseltech computer programming gasket normally used for another purpose to highlight the letters in a message hidden within a set of letters on a separate sheet.
A message transcribed using a programming gasket grille cypher is extremely difficult to decipher using traditional cryptographic methods. Both the programming gasket and backing sheet message are made to be indistinguishable from other data of their type (i.e. the gasket will be part of a functional program), and messages encoded as such are nearly impossible to decipher without both elements present. The necessity of programming knowledge limits the construction of new grilles. Choosing a pre-made section of programming gasket for this purpose reduces the time required to make a cypher, but it also increases the risk that the chosen section will be picked at random during a 'brute force' decoding attempt.

Writing System

In general, Guild Pidgin are written for use as the lettered sheet, while the programming gasket is encoded for some other purpose for machines using the Data Engines Limited computing architecture. These choices make the use of programming gasket grille cyphers appealing to agents from the Commonwealth of C, as both Guild Pidgin and programming gaskets are already familiar parts of the administrative functions of the Commonwealth government. At the same time, a single gasket or page of notes in Pidgin would not draw suspicion if encountered in other regions of the Manifold due to the ubiquity of the Navigator's Guild - and, in fact, the serious reputation of that organization might even dissuade further investigation.
For this same reason, the cypher also sees occasional use by Guild members seeking to convey information to their superiors without drawing the attention of their current clients. For example, a navigator might use his current guild contract card as a grille and compose a message warning that the clients are going to renege on the terms of that card and are not to be trusted for further business.

Root Languages

• Guild Pidgin