Atbash

Atbasch (also Atbash, Hebrew אתבש ) is a community based on the Hebrew alphabet simple method for encryption or decryption of a text. The original Kabbalistic method also served to reveal a hidden meaning in religious texts believed.

The name Atbasch is derived from the first two and last letters of the Hebrew writing system (ATB - Sch) and illustrates both the procedure in which the first letter ( Aleph ) is swapped with the last letter ( Tav ), the second letter ( Beth ) is swapped with the penultimate letter ( shin ), etc.

The Atbasch - value is the numeric value of the corresponding opposite sign, because Hebrew characters at the same time have a numerical value of Aleph (1) and Taw (400 ) have the Atbasch value 400 and 1

Properties

Atbasch is one of the simple mono alphabetic substitution method and is a variant of the Caesar cipher (inverted or reverted Caesar cipher ).

A special feature is that Atbasch is a involutorisches method, ie encryption and decryption method are identical. Therefore, it suffices to apply the Atbasch substitution for a second time on the ciphertext, to regain the original text.

Since the Atbasch is a solid method and allows no key-dependent variations, a cryptographic security is virtually non-existent.

ATBaSch

Principle of Atbasch applied to the Latin alphabet:

Atbasch of the Hebrew alphabet and its German transcription: ( The name derives from the first two to swap pairs of letters. Aleph with Taw and Beth Sch)

Example:

Variant Albam

Principle of Albam, applied to the Latin alphabet:

Albam (Hebrew אלבם ) is the ATBaSch similar encryption method. Comprised of 22 characters Hebrew alphabet is divided into two halves, each 11 letters ( א - כ and ל - ת ) divided, they will be assigned directly to each other.

Scheme of substitutions in the encryption method Albam: ( The name derives from the first two are also here to swap pairs of letters: Aleph Lamed with Beth with Mem )

The Albam method is equivalent in function to the Caesar cipher ROT13 the Latin alphabet. By shifting the character by half width alphabet are encryption and decryption, the same as with the Atbasch method.

Jewish tradition

Atbasch, Albam and similar techniques were used primarily as cryptographic techniques, but were initially hermeneutical approaches to the sacred texts ( see also PaRDeS and Ginat ).

Detail with these methods from the perspective of cryptography to Shmuel Archevolti dealt in the 30th chapter of his book Arugat ha - bosem which Johann the Younger Buxtorf translated into Latin and his edition of the Kuzari of Judah ha -Levi was handed out ( output Basel 1660).