AES
The SubBytes step, one of four stages in a round of AES
General
Designer(s):	Vincent Rijmen, Joan Daemen
First published:	1998
Derived from:	Square
Successor(s):	Anubis, Grand Cru
Certification:	AES winner, CRYPTREC, NESSIE
Cipher detail
Key size(s):	128, 192 or 256 bits[1]
Block size(s):	128 bits[2]
Structure:	Substitution-permutation network
Rounds:	10, 12 or 14 (depending on key size)
Best public cryptanalysis
A related-key attack can break up to 9 rounds of 256-bit AES. A chosen-plaintext attack can break 8 rounds of 192- and 256-bit AES, and 7 rounds of 128-bit AES. (Ferguson et al, 2000).

In cryptography, the Advanced Encryption Standard (AES), also known as Rijndael, is a block cipher adopted as an encryption standard by the U.S. government. It has been analyzed extensively and is now used widely worldwide^[3] as was the case with its predecessor, the Data Encryption Standard (DES). AES was announced by National Institute of Standards and Technology (NIST) as U.S. FIPS PUB 197 (FIPS 197) on November 26, 2001 after a 5-year standardization process (see Advanced Encryption Standard process for more details). It became effective as a standard May 26, 2002. As of 2006, AES is one of the most popular algorithms used in symmetric key cryptography. It is available by choice in many different encryption packages. Image File history File links AES-SubBytes. ... Together with Joan Daemen, Vincent Rijmen designed the Rijndael block cipher, which was selected as the Advanced Encryption Standard in 2000. ... Joan Daemen (born 1965) is a Belgian cryptographer and one of the designers of Rijndael, the Advanced Encryption Standard (AES), together with Vincent Rijmen. ... Year 1998 (MCMXCVIII) was a common year starting on Thursday (link will display full 1998 Gregorian calendar). ... In cryptography, Square (sometimes written SQUARE) is a block cipher invented by Joan Daemen and Vincent Rijmen. ... Anubis is a block cipher designed by Vincent Rijmen and Paulo S. L. M. Barreto as an entrant in the NESSIE project. ... In cryptography, Grand Cru is a block cipher invented in 2000 by Johan Borst. ... The Advanced Encryption Standard (AES), the block cipher ratified as a standard by National Institute of Standards and Technology (NIST), was chosen using a process markedly more open and transparent than its predecessor, the ageing Data Encryption Standard (DES). ... CRYPTREC is the Cryptography Research and Evaluation Committee set up by the Japanese Government to evaluate and recommend cryptographic techniques for government and industrial use. ... NESSIE (New European Schemes for Signatures, Integrity and Encryption) was a European research project funded from 2000–2003 to identify secure cryptographic primitives. ... In cryptography, the key size (alternatively key length) is the size of the digits used to create an encrypted text; it is therefore also a measure of the number of possible keys which can be used in a cipher, and the number of keys which must be tested to break... In modern cryptography, symmetric key ciphers are generally divided into stream ciphers and block ciphers. ... In cryptography, an SP-network, or substitution-permutation network (SPN), is a series of linked mathematical operations used in block cipher algorithms such as AES. These networks consist of S-boxes and P-boxes that transform blocks of input bits into output bits. ... Cryptanalysis (from the Greek kryptós, hidden, and analýein, to loosen or to untie) is the study of methods for obtaining the meaning of encrypted information, without access to the secret information which is normally required to do so. ... In cryptography, a related-key attack is any form of cryptanalysis where the attacker can observe the operation of a cipher under several different keys whose values are initially unknown, but where some mathematical relationship connecting the keys is known to the attacker. ... A chosen plaintext attack is any form of cryptanalysis which presumes that the attacker has the capability to choose arbitrary plaintexts to be encrypted and obtain the corresponding ciphertexts. ... The German Lorenz cipher machine, used in World War II for encryption of very high-level general staff messages Cryptography (or cryptology; derived from Greek κρυπτός kryptós hidden, and the verb γράφω gráfo write or λεγειν legein to speak) is the study of message secrecy. ... Encryption Decryption In cryptography, a block cipher is a symmetric key cipher which operates on fixed-length groups of bits, termed blocks, with an unvarying transformation. ... Encrypt redirects here. ... This article describes the government of the United States. ... The Data Encryption Standard (DES) is a cipher (a method for encrypting information) selected as an official Federal Information Processing Standard (FIPS) for the United States in 1976, and which has subsequently enjoyed widespread use internationally. ... NIST logo The National Institute of Standards and Technology (NIST, formerly known as The National Bureau of Standards) is a non-regulatory agency of the United States Department of Commerce’s Technology Administration. ... Federal Information Processing Standards (FIPS) are publicly announced standards developed by the U.S. Federal government for use by all (non-military) government agencies and by government contractors. ... is the 330th day of the year (331st in leap years) in the Gregorian calendar. ... Year 2001 (MMI) was a common year starting on Monday (link displays the 2001 Gregorian calendar). ... The Advanced Encryption Standard (AES), the block cipher ratified as a standard by National Institute of Standards and Technology (NIST), was chosen using a process markedly more open and transparent than its predecessor, the ageing Data Encryption Standard (DES). ... is the 146th day of the year (147th in leap years) in the Gregorian calendar. ... Also see: 2002 (number). ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... In mathematics, computing, linguistics, and related disciplines, an algorithm is a finite list of well-defined instructions for accomplishing some task that, given an initial state, will terminate in a defined end-state. ... Symmetric-key algorithms are a class of algorithms for cryptography that use trivially related cryptographic keys for both decryption and encryption. ...

The cipher was developed by two Belgian cryptographers, Joan Daemen and Vincent Rijmen, and submitted to the AES selection process under the name "Rijndael", a portmanteau of the names of the inventors. (Rijndael is pronounced [rɛindaːl], which sounds almost like "Rhine dahl").^[4] Joan Daemen (born 1965) is a Belgian cryptographer and one of the designers of Rijndael, the Advanced Encryption Standard (AES), together with Vincent Rijmen. ... Together with Joan Daemen, Vincent Rijmen designed the Rijndael block cipher, which was selected as the Advanced Encryption Standard in 2000. ... A portmanteau (IPA: ) is a word or morpheme that fuses two or more words or word parts to give a combined or loaded meaning. ...

Development

Rijndael was a refinement of Square, an earlier design by Daemen and Rijmen. Square was a development from Shark. In cryptography, Square (sometimes written SQUARE) is a block cipher invented by Joan Daemen and Vincent Rijmen. ... In cryptography, SHARK is a block cipher identified as one of the predecessors of Rijndael (the Advanced Encryption Standard). ...

Unlike its predecessor DES, Rijndael is a substitution-permutation network, not a Feistel network. AES is fast in both software and hardware, is relatively easy to implement, and requires little memory. As a new encryption standard, it is currently being deployed on a large scale.
In cryptography, an SP-network, or substitution-permutation network (SPN), is a series of linked mathematical operations used in block cipher algorithms such as AES. These networks consist of S-boxes and P-boxes that transform blocks of input bits into output bits. ... In cryptography, a Feistel cipher is a block cipher with a particular structure, named after IBM cryptographer Horst Feistel; it is also commonly known as a Feistel network. ... Software redirects here. ... For other uses, see Hardware (disambiguation). ... The terms storage (U.K.) or memory (U.S.) refer to the parts of a digital computer that retain physical state (data) for some interval of time, possibly even after electrical power to the computer is turned off. ...

Description of the cipher

Strictly speaking, AES is not precisely Rijndael (although in practice they are used interchangeably) as Rijndael supports a larger range of block and key sizes; AES has a fixed block size of 128 bits and a key size of 128, 192 or 256 bits, whereas Rijndael can be specified with key and block sizes in any multiple of 32 bits, with a minimum of 128 bits and a maximum of 256 bits. In modern cryptography, symmetric key ciphers are generally divided into stream ciphers and block ciphers. ... In cryptography, the key size (alternatively key length) is the size of the digits used to create an encrypted text; it is therefore also a measure of the number of possible keys which can be used in a cipher, and the number of keys which must be tested to break... This article is about the unit of information. ...

Due to the fixed block size of 128 bits, AES operates on a 4×4 array of bytes, termed the state (versions of Rijndael with a larger block size have additional columns in the state). Most of AES calculations are done in a special finite field. In computer science a byte (pronounced bite) is a unit of measurement of information storage, most often consisting of eight bits. ... Arithmetic in a finite field is different from standard integer arithmetic. ...

High-level cipher algorithm

• KeyExpansion using Rijndael's key schedule
• Initial Round
  • AddRoundKey
• Rounds

1. SubBytes — a non-linear substitution step where each byte is replaced with another according to a lookup table.
2. ShiftRows — a transposition step where each row of the state is shifted cyclically a certain number of steps.
3. MixColumns — a mixing operation which operates on the columns of the state, combining the four bytes in each column
4. AddRoundKey — each byte of the state is combined with the round key; each round key is derived from the cipher key using a key schedule.

• Final Round (no MixColumns)

1. SubBytes
2. ShiftRows
3. AddRoundKey

This article or section is in need of attention from an expert on the subject. ... This article describes the S-box used by the Rijndael cryptographic algorithm. ... The key-schedule of DES (<<< denotes a left rotation) In cryptography, the so-called product ciphers are a certain kind of ciphers, where the (de-)ciphering of data is done in rounds. The general setup of each round is the same, except for some hard-coded parameters and a part...

The SubBytes step

In the SubBytes step, each byte in the state is replaced with its entry in a fixed 8-bit lookup table, S; b_ij = S(a_ij).

In the SubBytes step, each byte in the array is updated using an 8-bit substitution box, the Rijndael S-box. This operation provides the non-linearity in the cipher. The S-box used is derived from the multiplicative inverse over GF(2⁸), known to have good non-linearity properties. To avoid attacks based on simple algebraic properties, the S-box is constructed by combining the inverse function with an invertible affine transformation. The S-box is also chosen to avoid any fixed points (and so is a derangement), and also any opposite fixed points. Image File history File links AES-SubBytes. ... Image File history File links AES-SubBytes. ... In cryptography, a substitution box (or S-box) is a basic component of symmetric key algorithms. ... This article describes the S-box used by the Rijndael cryptographic algorithm. ... This article is about algorithms for encryption and decryption. ... The reciprocal function: y = 1/x. ... In abstract algebra, a finite field or Galois field (so named in honor of Évariste Galois) is a field that contains only finitely many elements. ... In geometry, an affine transformation or affine map (from the Latin, affinis, connected with) between two vector spaces (strictly speaking, two affine spaces) consists of a linear transformation followed by a translation: In the finite-dimensional case each affine transformation is given by a matrix A and a vector b... In combinatorics, a derangement is a permutation &#966; of a set S (i. ...

The ShiftRows step

In the ShiftRows step, bytes in each row of the state are shifted cyclically to the left. The number of places each byte is shifted differs for each row.

The ShiftRows step operates on the rows of the state; it cyclically shifts the bytes in each row by a certain offset. For AES, the first row is left unchanged. Each byte of the second row is shifted one to the left. Similarly, the third and fourth rows are shifted by offsets of two and three respectively. For the block of size 128 bits and 192 bits the shifting pattern is the same. In this way, each column of the output state of the ShiftRows step is composed of bytes from each column of the input state. (Rijndael variants with a larger block size have slightly different offsets). In the case of the 256-bit block, the first row is unchanged and the shifting for second, third and fourth row is 1 byte, 3 byte and 4 byte respectively - although this change only applies for the Rijndael cipher when used with a 256-bit block, which is not used for AES. Image File history File links AES-ShiftRows. ... Image File history File links AES-ShiftRows. ... In computer science, an offset within an array or other data structure object is an integer indicating the distance (displacement) from the beginning of the object up until a given element or point, presumably within the same object. ...

The MixColumns step

In the MixColumns step, each column of the state is multiplied with a fixed polynomial c(x).

In the MixColumns step, the four bytes of each column of the state are combined using an invertible linear transformation. The MixColumns function takes four bytes as input and outputs four bytes, where each input byte affects all four output bytes. Together with ShiftRows, MixColumns provides diffusion in the cipher. Each column is treated as a polynomial over GF(2⁸) and is then multiplied modulo x⁴ + 1 with a fixed polynomial c(x) = 3x³ + x² + x + 2. The MixColumns step can also be viewed as a multiplication by a particular MDS matrix in Rijndael's finite field. Image File history File links AES-MixColumns. ... Image File history File links AES-MixColumns. ... In mathematics, a linear transformation (also called linear map or linear operator) is a function between two vector spaces that preserves the operations of vector addition and scalar multiplication. ... In cryptography, confusion and diffusion are two properties of the operation of a secure cipher which were identified by Shannon in his paper, Communication Theory of Secrecy Systems published in 1949. ... An MDS matrix (Maximum Distance Separable) is a matrix representing a function with certain diffusion properties that have useful applications in cryptography. ... Arithmetic in a finite field is different from standard integer arithmetic. ...

This process is described further in the article Rijndael mix columns. The MixColumns operation performed by the Rijndael cipher, along with the shift-rows step, is the primary source of diffusion in Rijndael. ...

The AddRoundKey step

In the AddRoundKey step, each byte of the state is combined with a byte of the round subkey using the XOR operation (⊕).

In the AddRoundKey step, the subkey is combined with the state. For each round, a subkey is derived from the main key using Rijndael's key schedule; each subkey is the same size as the state. The subkey is added by combining each byte of the state with the corresponding byte of the subkey using bitwise XOR. Image File history File links AES-AddRoundKey. ... Image File history File links AES-AddRoundKey. ... Exclusive disjunction (usual symbol xor) is a logical operator that results in true if one of the operands (not both) is true. ... A key is a piece of information that controls the operation of a cryptography algorithm. ... This article or section is in need of attention from an expert on the subject. ... Exclusive disjunction (usual symbol xor) is a logical operator that results in true if one of the operands (not both) is true. ...

Optimization of the cipher

On systems with 32-bit or larger words, it is possible to speed up execution of this cipher by combining SubBytes and ShiftRows with MixColumns, and transforming them into a sequence of table lookups. This requires four 256-entry 32-bit tables, which utilizes a total of four kibibytes (4096 bytes) of memory--a kibibyte for each table. A round can now be done with 16 table lookups and 12 32-bit exclusive-or operations, followed by four 32-bit exclusive-or operations in the AddRoundKey step. A kibibyte (a contraction of kilo binary byte) is a unit of information or computer storage, commonly abbreviated KiB (never kiB). 1 kibibyte = 210 bytes = 1,024 bytes The kibibyte is closely related to the kilobyte, which can be used either as a synonym for kibibyte or to refer to...

If the resulting four kibibyte table size is too large for a given target platform, the table lookup operation can be performed with a single 256-entry 32-bit table by the use of circular rotates.

Using a byte-oriented approach it is possible to combine the SubBytes, ShiftRows, and MixColumns steps into a single round operation.

Security

As of 2006, the only successful attacks against AES have been side channel attacks. The National Security Agency (NSA) reviewed all the AES finalists, including Rijndael, and stated that all of them were secure enough for US Government non-classified data. In June 2003, the US Government announced that AES may be used for classified information: In cryptography, a side channel attack is any attack based on information gained from the physical implementation of a cryptosystem, rather than theoretical weaknesses in the algorithms (compare cryptanalysis). ... “NSA” redirects here. ... ... A typical classified document. ...

"The design and strength of all key lengths of the AES algorithm (i.e., 128, 192 and 256) are sufficient to protect classified information up to the SECRET level. TOP SECRET information will require use of either the 192 or 256 key lengths. The implementation of AES in products intended to protect national security systems and/or information must be reviewed and certified by NSA prior to their acquisition and use." — [2]

This marks the first time that the public has had access to a cipher approved by NSA for encryption of TOP SECRET information. Many public products use 128-bit secret keys by default; it is possible that NSA suspects a fundamental weakness in keys this short, or they may simply prefer a safety margin for top secret documents (which may require security decades into the future).

The most common way to attack block ciphers is to try various attacks on versions of the cipher with a reduced number of rounds. AES has 10 rounds for 128-bit keys, 12 rounds for 192-bit keys, and 14 rounds for 256-bit keys. By 2006, the best known attacks were on 7 rounds for 128-bit keys, 8 rounds for 192-bit keys, and 9 rounds for 256-bit keys.^[5]

Some cryptographers worry about the security of AES. They feel that the margin between the number of rounds specified in the cipher and the best known attacks is too small for comfort. There is a risk that some way to improve such attacks might be found and then the cipher could be broken. In this meaning, a cryptographic "break" is anything faster than an exhaustive search, thus an attack against a 128-bit-key AES requiring 'only' 2¹²⁰ operations (compared to 2¹²⁸ possible keys) would be considered a break even though it would be, at present, quite infeasible. In practical application, any break of AES which is only that 'good' would be irrelevant. At present, such concerns can be ignored. The largest publicly-known brute force attack has been against a 64-bit RC5 key by distributed.net. Cryptanalysis (from the Greek kryptós, hidden, and analýein, to loosen or to untie) is the study of methods for obtaining the meaning of encrypted information, without access to the secret information which is normally required to do so. ... The EFFs US$250,000 DES cracking machine contained over 1,800 custom chips and could brute force a DES key in a matter of days — the photograph shows a DES Cracker circuit board fitted with several Deep Crack chips. ... The EFFs US$250,000 DES cracking machine contained over 1,800 custom chips and could brute force a DES key in a matter of days — the photograph shows a DES Cracker circuit board fitted with several Deep Crack chips. ... RC5 is a block cipher notable for its simplicity. ... The distributed. ...

Other debate centers around the mathematical structure of AES. Unlike most other block ciphers, AES has a very neat algebraic description.[3] This has not yet led to any attacks, but some researchers feel that basing a cipher on a new hardness assumption is risky. This has led Ferguson, Schroeppel, and Whiting to write, "...we are concerned about the use of Rijndael [AES] in security-critical applications."^[6] For other meanings of mathematics or uses of math and maths, see Mathematics (disambiguation) and Math (disambiguation). ... This article is about the branch of mathematics. ...

In 2002, a theoretical attack, termed the "XSL attack", was announced by Nicolas Courtois and Josef Pieprzyk, showing a potential weakness in the AES algorithm.^[7] Several cryptography experts have found problems in the underlying mathematics of the proposed attack, suggesting that the authors may have made a mistake in their estimates. Whether this line of attack can be made to work against AES remains an open question. At present, the XSL attack against AES appears speculative; it is unlikely that the current attack could be carried out in practice. Also see: 2002 (number). ... New Scientist magazine featured the XSL attack in June 2003 with an article billed as Cipher crisis: the end of internet privacy. In cryptography, the XSL attack is a method of cryptanalysis for block ciphers. ... Nicolas Courtois is a cryptographer who works on cryptosystems and cryptographic attacks based on multivariate polynomial equations over finite fields. ... Josef Pieprzyk is a professor at Macquarie University in Sydney, Australia. ...

Side channel attacks

Side channel attacks do not attack the underlying cipher, but attack implementations of the cipher on systems which inadvertently leak data. There are several such known attacks on AES. In cryptography, a side channel attack is any attack based on information gained from the physical implementation of a cryptosystem, rather than theoretical weaknesses in the algorithms (compare cryptanalysis). ...

In April 2005, D.J. Bernstein announced a cache timing attack that he used to break a custom server that used OpenSSL's AES encryption. The custom server was designed to give out as much timing information as possible, and the attack required over 200 million chosen plaintexts. Some say the attack is not practical over the internet with a distance of one or more hops;^[8] Bruce Schneier called the research a "nice timing attack."^[9] Daniel Julius Bernstein (sometimes known simply as djb; born October 29, 1971) is a professor at the University of Illinois at Chicago, a mathematician, a cryptologist, and a programmer. ... OpenSSL is an open source implementation of the SSL and TLS protocols. ... Bruce Schneier Bruce Schneier (born January 15, 1963) is an American cryptographer, computer security specialist, and writer. ...

In October 2005, Dag Arne Osvik, Adi Shamir and Eran Tromer presented a paper demonstrating several cache timing attacks(PDF file) against AES. One attack was able to obtain an entire AES key after only 800 operations triggering encryptions, in a total of 65 milliseconds. This attack requires the attacker to be able to run programs on the same system that is performing AES This article does not cite any references or sources. ... PDF is an abbreviation with several meanings: Portable Document Format Post-doctoral fellowship Probability density function There also is an electronic design automation company named PDF Solutions. ...

FIPS Validation

The Cryptographic Module Validation Program (CMVP) is operated jointly by the United States Government's National Institute of Standards and Technology (NIST) Computer Security Division and the Communications Security Establishment (CSE) of the Government of Canada. The use of validated cryptographic modules is required by the United States Government for all unclassified uses of cryptography. The Government of Canada also recommends the use of FIPS 140 validated cryptographic modules in unclassified applications of its departments. The Cryptographic Module Validation Program (CMVP) is an Information Technology (IT) security accrediation program for cryptographic modules produced by private sector vendors who seek to have their products certified for use in government departments and regulated industries (such as financial and health_care institutions) that collect, store, transfer, share and disseminate... NIST logo The National Institute of Standards and Technology (NIST, formerly known as The National Bureau of Standards) is a non-regulatory agency of the United States Department of Commerce’s Technology Administration. ... The CSE badge The Communications Security Establishment or CSE is an intelligence agency of the Canadian government, charged with the duty of keeping track of foreign signals intelligence. ... FIPS 140 (Federal Information Processing Standards Publication 140) is a United States federal standard that specifies security requirements for cryptography modules. ...

Although NIST publication 197 ("FIPS 197") is the unique document that covers the AES algorithm, vendors typically approach the CMVP under FIPS 140 and ask to have several algorithms (such as 3DES or SHA1) validated at the same time. Therefore, it is rare to find cryptographic modules that are uniquely FIPS 197 validated and NIST itself does not generally take the time to list FIPS 197 validated modules separately on its public web site. Instead, FIPS 197 validation is typically just listed as an "FIPS approved: AES" notation (with a specific FIPS 197 certificate number) in the current list of FIPS 140 validated cryptographic modules. In cryptography, Triple DES (also 3DES) is a block cipher formed from the Data Encryption Standard (DES) cipher. ... The SHA (Secure Hash Algorithm) family is a set of related cryptographic hash functions designed by the National Security Agency (NSA) and published by the National Institute of Standards and Technology (NIST). ...

FIPS validation is challenging to achieve both technically and fiscally. There is a standardized battery of tests as well as an element of source code review that must be passed over a period of several days. The cost to perform these tests through an approved laboratory can be significant (e.g., well over $10,000 US) and does not include the time it takes to write, test, document and prepare a module for validation. After validation, modules must be resubmitted and reevaluated if they are changed in any way.

See also

• Serpent
• Twofish
• Data Encryption Standard
• Advanced Encryption Standard process
• Security and Trust Services API for J2ME

Serpent is a symmetric key block cipher which was a finalist in the Advanced Encryption Standard contest, where it came second to Rijndael. ... In cryptography, Twofish is a symmetric key block cipher with a block size of 128 bits and key sizes up to 256 bits. ... The Data Encryption Standard (DES) is a cipher (a method for encrypting information) selected as an official Federal Information Processing Standard (FIPS) for the United States in 1976, and which has subsequently enjoyed widespread use internationally. ... The Advanced Encryption Standard (AES), the block cipher ratified as a standard by National Institute of Standards and Technology (NIST), was chosen using a process markedly more open and transparent than its predecessor, the ageing Data Encryption Standard (DES). ... The Security and Trust Services API for J2ME (SATSA) is a collection of Java ME-based APIs that provides compliant devices with additional cryptographic security features. ...

Notes and references

1. ^ Key sizes of 128, 160, 192, 224, and 256 bits are supported by the Rijndael algorithm, but only the 128, 192, and 256-bit key sizes are specified in the AES standard.
2. ^ Block sizes of 128, 160, 192, 224, and 256 bits are supported by the Rijndael algorithm, but only the 128-bit block size is specified in the AES standard.
3. ^ NIST reports measurable success of Advanced Encryption Standard.
4. ^ {{cite web |url=http://rijndael.info/audio/rijndael_pronunciation.wav |title='Rijndael' pronunciation
5. ^ John Kelsey, Stefan Lucks, Bruce Schneier, Mike Stay, David Wagner, and Doug Whiting, Improved Cryptanalysis of Rijndael, Fast Software Encryption, 2000 pp213–230 [1]
6. ^ Niels Ferguson, Richard Schroeppel, Doug Whiting (2001). "A simple algebraic representation of Rijndael" (PDF/PostScript). Proceedings of Selected Areas in Cryptography, 2001, Lecture Notes in Computer Science: pp. 103–111, Springer-Verlag. Retrieved on 2006-10-06. 
7. ^ Bruce Schneier. AES News, Crypto-Gram Newsletter, September 15, 2002. Retrieved on 2007-07-27.
8. ^ Louis Scheffer (2005-04-16). "Re: Successful remote AES key extraction". sci.crypt. (Google Groups).
9. ^ Bruce Schneier. AES Timing Attack. Retrieved on 2007-03-17.

• Nicolas Courtois, Josef Pieprzyk, "Cryptanalysis of Block Ciphers with Overdefined Systems of Equations". pp267–287, ASIACRYPT 2002.
• Joan Daemen and Vincent Rijmen, "The Design of Rijndael: AES - The Advanced Encryption Standard." Springer-Verlag, 2002. ISBN 3-540-42580-2.

John Kelsey is a cryptographer currently working at NIST. His research interests include cryptanalysis and design of symmetric cryptography primitives (block ciphers, stream ciphers, cryptographic hash functions, MACs), analysis and design of cryptographic protocols, cryptographic random number generation, electronic voting, side-channel attacks on cryptography implementations, and anonymizing communications systems. ... Stefan Lucks is a cryptographer and cryptanalyst most well known for his attack on Triple DES, and for extending Lars Knudsens Square attack to Twofish a cipher outside the Square family, thus founding integral cryptanalysis. ... Bruce Schneier Bruce Schneier (born January 15, 1963) is an American cryptographer, computer security specialist, and writer. ... David Wagner David A. Wagner (1974) is an Assistant Professor of Computer Science at the University of California, Berkeley and a well-known researcher in cryptography. ... Fast Software Encryption, often abbreviated FSE, is a workshop for cryptography research, focussed on symmetric-key cryptography with an emphasis on fast, practical techniques, as opposed to theory. ... Niels Ferguson is a Dutch cryptographic engineer and consultant. ... Richard Schroeppel is an American mathematician who discovered the number of 5x5 magic squares. ... PDF is an abbreviation with several meanings: Portable Document Format Post-doctoral fellowship Probability density function There also is an electronic design automation company named PDF Solutions. ... For the literary term, see Postscript. ... Selected Areas in Cryptography (SAC) is a series of international cryptography workshops held annually in Canada, every August since 1994. ... The Springer-Verlag (pronounced SHPRING er FAIR lahk) was a worldwide publishing company base in Germany. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 279th day of the year (280th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 208th day of the year (209th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 76th day of the year (77th in leap years) in the Gregorian calendar. ... Asiacrypt (also ASIACRYPT) is an important international conference for cryptography research. ...

External links

• The Rijndael Page (Forwards automatically to the AES Lounge; use old version link to browse)
• The Rijndael Page (old version)
• Literature survey on AES
• Recordings of the pronunciation of "Rijndael" (85 KB wav file)
• The archive of the old official AES website
• FIPS PUB 197: the official AES standard (PDF file)
• John Savard's description of the AES algorithm
• Animation of the 128-bit AES encryption process
• Very detailed AES tutorial with implementation in C

WAV (or WAVE), short for Waveform audio format, is a Microsoft and IBM audio file format standard for storing audio on PCs. ... “PDF” redirects here. ...

Implementations

• Current list of FIPS 140 validated cryptographic modules with validated AES implementations (hosted by NIST) - Most of these involve a commercial implementation of AES algorithms. Look for "FIPS-approved algorithms" entry in the "Level / Description" column followed by "AES" and then a specific certificate number.

C/ASM Library

• GPL-licensed Nettle library also includes an AES implementation
• LGPL-licensed written in C
• A byte-oriented public domain in C
• BSD licensed from Brian Gladman
• Public-domain from D.J. Bernstein
• Public domain C from Paulo Barreto
• Public domain C from Philip J. Erdelsky

C++ Library

• Crypto++ A comprehensive C++ semi-public-domain implementation of encryption and hash algorithms. FIPS validated
• Chris Lomont's public-domain version of AES

Java

• Bouncy Castle Crypto Library

Bouncy castle is a collection of API (Application Programming Interface) used in cryptography. ...

JavaScript

• Clipperz Crypto Library, includes an efficient implementation.
• Direct implementation of standard transparently coded, with counter mode of operation
• Calculator showing intermediate values

Other Languages

• Martin Offenwanger's GPL-licensed AES source code written in Delphi
• "Keep Your Data Secure with the New Advanced Encryption Standard" A detailed explanation with C# implementation by James D. McCaffrey.
• LGPL 128bit Implementation in PHP (Registration required)

James D. McCaffrey (1950 -) is a software engineer and author specializing in software test automation and mathematical combinatorics. ...

File Based Encryption

• OpenSSL includes AES cipher support as of version 0.9.7 and is dual-licensed under the terms of the OpenSSL License and the original SSLeay license. FIPS validated via IBM
• Peter Selingers ccrypt file encryption utility for UNIX, GPL-licensed