TextHide Server

• several rephrasing aspects like word order and synonym replacement can be used in such a way that secret information is kept even if an attacker rephrases the text
• text collections available from the following sectors: vacation, politics, business, jokes, anecdotes, glosses, news/newspaper articles (these texts can be used automatically as banal texts)
• integrated public key cryptography (encryption with public and secret keys; high security since secret keys are not exchanged); method is based on the RSA method for key exchange as well as the brand-new Twofish method as block cypherer (stream encryption)
• management of public keys (from correspondent partners) and secret keys
• integrated in MS-Office: TextHide functionality is available via simple short cuts and via buttons in Microsoft Word
• gigantically long keys from 48 bit (Netscape key length for "safe" Internet connections in Europe) up to 100 kBytes possible – these keys contain the information for reorganizing the dictionary (which words should be used more or less often); the resulting 10³⁰⁰⁰⁰ possible variants for rephrasing texts make this an extremely secure method. An attacker with a high performance computer would need in average 10²⁹⁹⁹⁰ years to decode the right secret message with such a long key by random testing. The earth has been existing for about 5 * 10⁹ years. If 100 000 = 10⁵ high performance computers would be assigned to this problem, they would approximately need 10²⁰⁰⁰ times longer than our earth has been existing. The public key method (RSA) works with up to 4096 bits key length, the block cypher (Twofish) with 256 bits key length.
• Prevention of false reports / wrong instructions: all messages/reports will systematically get hidden secret messages added. These secret messages can take the form of a validity control code to be checked automatically upon decryption. If the control code is wrong, the message / the instruction will be rejected. Alternatively, for manual validity checking, control words or sentences previously agreed upon can be hidden.

• Misleading eavesdroppers:

1. With messages to partners, which contain text as banal as the plainly transmitted text, the opposite or something drastically different of the message that is secretly encoded
2. Through the use of seemingly unencrypted messages instead of directly detectable encrypted messages

• several (encrypted) secret messages (for different addressees) can be encoded in the text
• rephrased text can be compressed down to about 25%. This means that a total inflation (compressed text with secret message hidden : secret data) of about 3 can be reached.
• it is selectable how strong the synonyms can deviate in their meaning within a group
• all dictionaries included for German, English, and French
• interactive rephrasal of texts from passive to active through checkbacks
• grammar correction
• rules for punctuation
• conversion from old to new German spelling convention

• integration of cryptography and steganography (encryption & hiding) in any network environments or as a component in applications
• adaptation of the method: support functionality for any self-generated dictionaries (any word lists or synonym groups can be converted by a program into the TextHide format), adapted steganographical methods, combinable with encryption and/or data compression
• free support and update service for 1 year

Percent worse as Twofish

• developed in the USA by a research team around crypto guru Bruce Schneier
• can be integrated in any kind of network environment or as a component in applications
• newest, most secure and unpatented technology
• additional RSA component with key management (to secure the key exchange for Twofish)
• encoding speed, time for key-specific calculations, code size, RAM consumption (main memory), ROM consumption (for example on a smart card) or amount of gates on a chip can be varied or rather traded off against each other. Increasing one of these values goes along with a worsening of one or more of the other values.
• method can be implemented on a Smartcard with less than 64 bytes of RAM and even less than 1400 Bytes of ROM; as a hardware solution less than 14000 gates will be needed