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The Data Encryption Standard (DES) is a block cipher that uses a symmetric key (shared secret) algorithm. DES is now considered to be insecure for many applications. This is chiefly due to the 56-bit key size being too small; in January, 1999, a group of computer experts collaborated to publicly break a DES key in 22 hours and 15 minutes. There are also some analytical results which demonstrate theoretical weaknesses in the cipher, although they are infeasible to mount in practice. The algorithm is believed to be practically secure in the form of "Triple DES". Triple DES uses a "key bundle" which comprises three DES keys, K1, K2 and K3, each of 56 bits (excluding parity bits).
The encryption algorithm is: ciphertext = EK3(DK2(EK1(plaintext)))
in other words, DES encrypt with K1, DES decrypt with K2, then DES encrypt with K3.
Decryption is the reverse: plaintext = DK1(EK2(DK3(ciphertext)))
in other words, decrypt with K3, encrypt with K2, then decrypt with K1.
Each triple encryption encrypts one block of 64 bits of data. The strongest application of Triple DES is to use 3 independent keys so that you get 3 x 56 = 168 independent key bits, but it is not uncommon to simplify the operation by just using two keys, making K1 and K3 the same but making sure K2 is independent of K1. This second Keying option provides less security than using 3 independent keys, with 2 x 56 = 112 key bits. This second option is stronger than simply DES encrypting twice, e.g. with K1 and K2, because it protects against meet-in-the-middle attacks.
In recent years, the DES cipher has been superseded by the Advanced Encryption Standard (AES). Furthermore, DES has been withdrawn as a standard by NIST (previously known as NBS).
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What authentication also uses the DES algorithm?
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What authentication also uses DES algorithm?
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What are the difference between DES and RSA algorithm?
DES is a symmetric cryptographic algorithm, while RSA is an asymmetric (or public key) cryptographic algorithm. Encryption and decryption is done with a single key in DES, while you use separate keys (public and private keys) in RSA. DES uses 56-bit keys for encryption while RSA uses 2600-bits of KEY
What is Difference between DES and RSA algorithm?
1. RSA comes under Asymmetric and DES comes under Symmetric 2. RSA is more secure than DES.
Which algorithm has the smallest key space?
DES Data Encryption Standard 56 bit
Different types Library of computer security related algorithm?
HMAC RSA SHA AES DES
What are the encryption algorithms used in ATM?
fot the past 25 years single des algorithm was used. But now triple des is used in atm cards for the encryption and decryption.
What is are the time complexity or space complexity of DES algorithm?
time complexity is 2^57..and space complexity is 2^(n+1).
What is the DES algorithm And what are its variants?
The original DES algorithm, I believe, did only two things bit shifting and bit substituion. It di these operations repeadtley and on a very nonlinear fashion. I guess kinda like putting scrabble letters in a bag and shaking them up. There are a couple variants I know of. Lucifer, which was developed by IBM in the 70s. And then there is Enigma.
Why the DES is slower in software?
I can only guess that you ask about the performance of the DES algorithm when implemented in software as opposed to hardware. Any algorithm that can be economically implemented in hardware will perform faster in hardware than software by orders of magnitude in the general case. Encryption algorithms such as DES are often based on a shift-combine-shift sequence, which is fairly easy to implement in hardware, but can take considerable processing time when implemented in software.
What does D'un autre cote il y a bien sur des inconvenients mean in french?
On the other hand, there are of course some drawbacks / inconveniences / disadvantages.
Why the DES is currently considered insecure?
DES is now considered to be insecure for many applications. This is chiefly due to the 56-bit key size being too small; in January, 1999, distributed.net and the Electronic Frontier Foundation collaborated to publicly break a DES key in 22 hours and 15 minutes (see chronology). There are also some analytical results which demonstrate theoretical weaknesses in the cipher, although they are infeasible to mount in practice. The algorithm is believed to be practically secure in the form of Triple DES, although there are theoretical attacks. In recent years, the cipher has been superseded by the Advanced Encryption Standard (AES). Furthermore, DES has been withdrawn as a standard by the National Institute of Standards and Technology (formerly the National Bureau of Standards).In some documentation, a distinction is made between DES as a standard and DES the algorithm which is referred to as the DEA (the Data Encryption Algorithm). When spoken, "DES" is either spelled out as an abbreviation (/ˌdiːˌiːˈɛs/), or pronounced as a one-syllable acronym (/ˈdɛz/).
