OMI cryptograph

The OMI cryptograph was a seven-rotor machine produced by Italian firm Ottico Meccanica Italiana.

The OMI cryptograph was a rotor cipher machine produced and sold by Italian firm Ottico Meccanica Italiana (OMI) in Rome.

The machine had seven rotors, including a reflecting rotor. The rotors stepped regularly. Each rotor could be assembled from two sections with different wiring: one section consisted of a "frame" containing ratchet notches, as well as some wiring, while the other section consisted of a "slug" with a separate wiring. The slug section fitted into the frame section, and different slugs and frames could be interchanged with each other. As a consequence, there were a large number of permutations for the rotor selection.

The machine was offered for sale during the 1960s .

References

Cipher A. Deavours and Louis Kruh, "Machine Cryptography and Modern Cryptanalysis", Artech House, 1985, pp. 146–147
F. L. Bauer, Decrypted Secrets, 2nd edition, Springer-Verlag, 2000, ISBN 3-540-66871-3, pp. 112,136.

Cipher machines

Rotor machines:	CCM Enigma M – 125 Fialka Hebern HX-63 KL-7 Lacida M-325 Mercury NEMA OMI Portex RED SIGABA SIGCUM Singlet Typex

Mechanical:	Bazeries cylinder C-36 C-52 CD-57 Cipher disk HC-9 Kryha Jefferson disk M-94 M-209 Reihenschieber Scytale

Teleprinter:	5-UCO BID 770 DUDEK KW-26 KW-37 Lorenz SZ 40/42 Siemens and Halske T52

Secure voice:	BID 150 FASCINATOR KY-3 KY-57 KY-58 KY-68 OMNI SCIP Sectéra Secure Module SIGSALY STE STU-II STU-III VINSON

Miscellaneous:	JADE KG-84 KL-43 Noreen PURPLE Pinwheel Rockex

Cryptography

History of cryptography Cryptanalysis Cryptography portal Outline of cryptography

Symmetric-key algorithm Block cipher Stream cipher Public-key cryptography Cryptographic hash function Message authentication code Random numbers Steganography