M8

M8 or M-8 may refer to:

Computing, electronics, and engineering

Rockets

Transport

Civilian

Military

M8 (cipher)

In cryptography, M8 is a block cipher designed by Hitachi in 1999. It is a modification of Hitachi's earlier M6 algorithm, designed for greater security and high performance in both hardware and 32-bit software implementations.

Like M6, M8 is a 10-round Feistel cipher with a block size of 64 bits. The round function can include bit rotations, XORs, and modular addition, but the structure of each round function used is determined by the key. Making these variations key-dependent is intended to make cryptanalysis more difficult (see FROG for a similar design philosophy).

References

M8 (rocket)

The M8 was a 4.5-inch (110 mm) rocket developed and used by the United States military during World War II. Produced in the millions, it was fired from both air- and ground-based launchers; it was replaced by the M16 rocket in 1945.

Development

The M8 rocket was developed by the National Defense Research Committee and the Army Ordnance Department in the early 1940s; at Picatinny Arsenal. Ground tests began in 1941, while the first air launch of the system was conducted in 1942, from a Curtiss P-40 pursuit aircraft. It was fin stabilized, and had a diameter of 4.5 in (110 mm).

The initial production model was given the Army designation of M8; improvements resulted in the M8A3, with a more powerful rocket engine and enlarged fins, and the T22, which had improved reliability and modifications to make the rocket safer.

Operational history

Entering service in 1943, the M8 family of rockets saw service with the United States Army, which classified the M8 as a "barrage rocket". The rocket was also widely used by the United States Army Air Forces. Over 2,500,000 of the M8 type rocket had been produced by the end of the war.