MDC

MDC may refer to:

MDC-2

In cryptography, MDC-2 (Modification Detection Code 2, sometimes called Meyer-Schilling) is a cryptographic hash function. MDC-2 is a hash function based on a block cipher with a proof of security in the ideal-cipher model. The length of the output hash depends on the underlying block cipher used.

Algorithm

For a given message to hash and a given block cipher encryption function , the MDC-2 algorithm proceeds as follows. Let be the block length, two different constants of size . If where each has size , then the hash of the message is given by:

for to :

• 
• 
• 
• 
• 
• 

return

MDC-2DES hashes

When MDC-2 uses the DES block cipher, the 128-bit (16-byte) MDC-2 hashes are typically represented as 32-digit hexadecimal numbers. The following demonstrates a 43-byte ASCII input and the corresponding MDC-2 hash:

Even a small change in the message will (with probability) result in a completely different hash, e.g. changing d to c:

The hash of the zero-length string is:

Patent issues

MDC-2 was covered by U.S. Patent 4,908,861, issued on March 13, 1990 but filed by IBM on August 28, 1987.
For this reason, support for MDC-2 has been disabled in OpenSSL on most Linux distributions and is not implemented by many other cryptographic libraries.

One-way compression function

In cryptography, a one-way compression function is a function that transforms two fixed-length inputs into a fixed-length output. The transformation is "one-way", meaning that it is difficult given a particular output to compute inputs which compress to that output. One-way compression functions are not related to data compression, which by definition can be inverted exactly (lossless compression) or approximately (lossy compression) to the original data.

One-way compression functions are for instance used in the Merkle–Damgård construction inside cryptographic hash functions.

One-way compression functions are often built from block ciphers. Some methods to turn any normal block cipher into a one-way compression function are Davies–Meyer, Matyas–Meyer–Oseas, Miyaguchi–Preneel (single-block-length compression functions) and MDC-2/Meyer–Schilling, MDC-4, Hirose (double-block-length compression functions). These methods are described in detail further down. (MDC-2 is also the name of a hash function patented by IBM.)

Super (2005 film)

Super (Telugu: సూపర్) is a 2005 Telugu heist-action-thriller film produced by Nagarjuna Akkineni on Annapurna Studios banner, written and directed by Puri Jagannadh. Starring Nagarjuna Akkineni, Ayesha Takia, Anushka Shetty, Sonu Sood in lead roles and music composed by Sandeep Chowta. The film was also dubbed into Hindi and was titled Robbery. The film recorded as Hit at box-office.

Plot

Akhil (Nagarjuna Akkineni) owns a call cab service. He falls in love with a doctor, Siri Valli (Ayesha Takia). Soon Siri Valli falls in love with Akhil as well. There is a hi-tech robber called Sonu (Sonu Sood) who steals money in a big way. Sonu used to work for Siri Valli's father and so adopts her as his sister after their family fall into bad times.

Incidentally, Akhil and Sonu are enemies. When Sonu realizes that Siri Valli is in deep love with his arch enemy Akhil, he asks her to put an end to their relationship and to never see him again. Siri Valli goes to Akhil's house to find out why Sonu and he are enemies. Akhil reveals his flashback:

Super (Neu! song)

Super is a single by German band Neu!, released in 1972. It failed to chart and has never been re-released, but has become a collector's item due to the rarity of the original vinyl 7". After the single's recording both the A and B side tracks were added to the album Neu! 2, which was released the following year.

Recording, Release & Remixing

Both tracks were recorded quickly at Conny Plank's studio in Cologne during the summer of 1972, six months after the release of Neu!'s debut album. Brain were pessimistic about the single's chances, and had to be convinced to release it by Dinger and Rother. When it was released, it was backed by only minimal promotion, and predictably failed to make any impact on the German music charts (though some Krautrock acts - such as Can - did have successful singles in the early '70s).

When Dinger and Rother returned to the studio in early 1973 to record Neu! 2, they decided to fill the second side of the new album with tape manipulated remixes of the Super/Neuschnee single. There have been several conflicting explanations as to why this was done, the most quoted being Dinger's assertion that:

.45 Super

The .45 Super is a large and powerful smokeless powder center fire metallic firearm cartridge developed in 1988 by Dean Grennell, a well-known writer in the firearms field as well as managing editor of Gun World magazine. Born of a desire to update and improve the 1906 era .45 ACP, the .45 Super cartridge is dimensionally identical with the older .45 ACP round. A notable difference is that it has a thicker case wall than its ACP brethren cartridge, and the Super is loaded to higher pressures, which makes it a substantially more powerful round than the standard .45 ACP. It offers an average 300 foot per second (ft/s) improvement in muzzle velocity. The cartridge was co-developed by Tom Fergerson and Ace Hindman.

Development history