- repeated plaintext digraphs
- повторяющиеся биграммы открытого текста.
English-Russian cryptological dictionary . 2014.
English-Russian cryptological dictionary . 2014.
cryptology — cryptologist, n. cryptologic /krip tl oj ik/, cryptological, adj. /krip tol euh jee/, n. 1. cryptography. 2. the science and study of cryptanalysis and cryptography. [1635 45; < NL cryptologia. See CRYPTO , LOGY] * * * Introduction … Universalium
Four-square cipher — The Four square cipher is a manual symmetric encryption technique. It was invented by famous French cryptographer Felix Delastelle.The technique encrypts pairs of letters ( digraphs ), and thus falls into a category of ciphers known as… … Wikipedia