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Logic-Crypto-Encryp. An Overview of Cryptography. As an aside, the AES selection process managed by NIST was very public. A similar project, the New European Schemes for Signatures, Integrity and Encryption (NESSIE), was designed as an independent project meant to augment the work of NIST by putting out an open call for new cryptographic primitives. NESSIE ran from about 2000-2003. While several new algorithms were found during the NESSIE process, no new stream cipher survived cryptanalysis.

As a result, the ECRYPT Stream Cipher Project (eSTREAM) was created, which has approved a number of new stream ciphers for both software and hardware implementation. Similar — but different — is the Japanese Government Cryptography Research and Evaluation Committees (CRYPTREC) efforts to evaluate algorithms submitted for government and industry applications. CAST-128/256: CAST-128, described in Request for Comments (RFC) 2144, is a DES-like substitution-permutation crypto algorithm, employing a 128-bit key operating on a 64-bit block. 3.3. Learn morse code. Substitution cipher. In cryptography, a substitution cipher is a method of encoding by which units of plaintext are replaced with ciphertext, according to a regular system; the "units" may be single letters (the most common), pairs of letters, triplets of letters, mixtures of the above, and so forth.

The receiver deciphers the text by performing an inverse substitution. Substitution ciphers can be compared with transposition ciphers. In a transposition cipher, the units of the plaintext are rearranged in a different and usually quite complex order, but the units themselves are left unchanged. By contrast, in a substitution cipher, the units of the plaintext are retained in the same sequence in the ciphertext, but the units themselves are altered.

There are a number of different types of substitution cipher. Simple substitution[edit] ROT13 is a Caesar cipher, a type of substitution cipher. Using this system, the keyword "zebras" gives us the following alphabets: A message of flee at once. we are discovered! ). Runic alphabets / Runes / Futhark. Little is known about the origins of the Runic alphabet, which is traditionally known as futhark after the first six letters. In Old Norse the word rune means 'letter', 'text' or 'inscription'. The word also means 'mystery' or 'secret' in Old Germanic languages and runes had a important role in ritual and magic. Here are some theories about the origins of runes: The alphabet was probably created independently rather than evolving from another alphabet. Runic writing was probably first used in southern Europe and was carried north by Germanic tribes.

The earliest known Runic inscriptions date from the 1st century AD, but the vast majority of Runic inscriptions date from the 11th century. Notable features The direction of writing in early Runic inscriptions is variable. Types of runic inscriptions include: There are a number of different Runic alphabets including: Elder Futhark Notes The letter k is also called kēnaz (torch) or kanō (skiff). Younger Futhork Danish Futhark Norwegian Futhark Links. Runic alphabet. Runology is the study of the runic alphabets, runic inscriptions, runestones, and their history. Runology forms a specialised branch of Germanic linguistics. The earliest runic inscriptions date from around AD 150. The characters were generally replaced by the Latin alphabet as the cultures that had used runes underwent Christianisation, by approximately AD 700 in central Europe and AD 1100 in Northern Europe. However, the use of runes persisted for specialized purposes in Northern Europe. Until the early 20th century, runes were used in rural Sweden for decorative purposes in Dalarna and on Runic calendars.

The three best-known runic alphabets are the Elder Futhark (around AD 150–800), the Anglo-Saxon Futhorc (AD 400–1100), and the Younger Futhark (AD 800–1100). Historically, the runic alphabet is a derivation of the Old Italic alphabets of antiquity, with the addition of some innovations. The process of transmission of the script is unknown. History and use[edit] Origins[edit] Theban alphabet. The Theban alphabet is a writing system with unknown origins which first came into publication in the 16th century. Publication history[edit] It was first published in Johannes Trithemius' Polygraphia (1518), in which it was attributed to Honorius of Thebes "as Pietro de Abano testifies in his greater fourth book". However, it is not known to be extant in any of the known writings attributed to d'Abano (1250-1316). Trithemius' student Heinrich Cornelius Agrippa (1486–1535) included it in his de Occulta Philosophia (Book III, chap. 29, 1531).[1] It is also not known to be found in any manuscripts of the writings of Honorius of Thebes (i.e.

Liber Iuratus Honorii, or The Sworn Book of Honorius), with the exception of the composite manuscript found in London, British Library Manuscript Sloane 3853, which however openly identifies Agrippa as its source. Uses and correlations[edit] Characters[edit] Notes[edit] External links[edit]