|
Boneh–Franklin Scheme
The Boneh–Franklin scheme is an identity-based encryption system proposed by Dan Boneh and Matthew K. Franklin in 2001. This article refers to the protocol version called BasicIdent. It is an application of pairings (Weil pairing) over elliptic curves and finite fields. Groups and parameters As the scheme bases upon pairings, all computations are performed in two groups, \textstyle G_1 and \textstyle G_2: For \textstyle G_1, let \textstyle p be prime, \textstyle p \equiv 2 \mod 3 and consider the elliptic curve \textstyle E: y^2 = x^3 + 1 over \textstyle \mathbb/p\mathbb. Note that this curve is not singular as \textstyle 4a^3+27b^2 = 27 = 3^3 only equals \textstyle 0 for the case \textstyle p = 3 which is excluded by the additional constraint. Let \textstyle q > 3 be a prime factor of \textstyle p + 1 (which is the order of \textstyle E) and find a point \textstyle P \in E of order \textstyle q. \textstyle G_1 is the set of points generated by \textstyle P: \textstyle \left\ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ID-based Encryption
ID-based encryption, or identity-based encryption (IBE), is an important primitive of ID-based cryptography. As such it is a type of public-key encryption in which the public key of a user is some unique information about the identity of the user (e.g. a user's email address). This means that a sender who has access to the public parameters of the system can encrypt a message using e.g. the text-value of the receiver's name or email address as a key. The receiver obtains its decryption key from a central authority, which needs to be trusted as it generates secret keys for every user. ID-based encryption was proposed by Adi Shamir in 1984. He was however only able to give an instantiation of identity-based signatures. Identity-based encryption remained an open problem for many years. The pairing-based Boneh–Franklin scheme and Cocks's encryption scheme based on quadratic residues both solved the IBE problem in 2001. Usage Identity-based systems allow any party to generate a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bilinear Diffie Hellman Problem
{{disambiguation ...
Bilinear may refer to: * Bilinear sampling (also called "bilinear filtering"), a method in computer graphics for choosing the color of a texture * Bilinear form, a type of mathematical function from a vector space to the underlying field * Bilinear interpolation, an extension of linear interpolation for interpolating functions of two variables on a rectilinear 2D grid * Bilinear map, a type of mathematical function between vector spaces * Bilinear transform, a method of transforming from the S to Z domain in control theory and signal processing * Bilinear transformation (other) Bilinear transformation may refer to: * Bilinear map or bilinear operator * Bilinear transform (signal processing), a type of conformal map used to switch between continuous-time and discrete-time representations * Möbius transformation (complex an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pairing-based Cryptography
Pairing-based cryptography is the use of a pairing between elements of two cryptographic groups to a third group with a mapping e :G_1 \times G_2 \to G_T to construct or analyze cryptographic systems. Definition The following definition is commonly used in most academic papers. Let F_q be a Finite field over prime q, G_1, G_2 two additive cyclic groups of prime order q and G_T another cyclic group of order q written multiplicatively. A pairing is a map: e: G_1 \times G_2 \rightarrow G_T , which satisfies the following properties: ; Bilinearity: \forall a,b \in F_q^*, P\in G_1, Q\in G_2:\ e\left(aP, bQ\right) = e\left(P, Q\right)^ ; Non-degeneracy: e \neq 1 ; Computability: There exists an efficient algorithm to compute e. Classification If the same group is used for the first two groups (i.e. G_1 = G_2), the pairing is called ''symmetric'' and is a mapping from two elements of one group to an element from a second group. Some researchers classify pairing instantiations int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Public-key Encryption Schemes
Public-key cryptography, or asymmetric cryptography, is the field of cryptographic systems that use pairs of related keys. Each key pair consists of a public key and a corresponding private key. Key pairs are generated with cryptographic algorithms based on mathematical problems termed one-way functions. Security of public-key cryptography depends on keeping the private key secret; the public key can be openly distributed without compromising security. In a public-key encryption system, anyone with a public key can encrypt a message, yielding a ciphertext, but only those who know the corresponding private key can decrypt the ciphertext to obtain the original message. For example, a journalist can publish the public key of an encryption key pair on a web site so that sources can send secret messages to the news organization in ciphertext. Only the journalist who knows the corresponding private key can decrypt the ciphertexts to obtain the sources' messages—an eavesdropp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tatsuaki Okamoto
Tatsuaki (written: , or ) is a masculine Japanese given name. Notable people with the name include: *, Japanese judoka *, Japanese Go player *, Japanese woodworker and lacquerware artist See also *TATSUAKI, a fashion label by Dan Liu Dan Liu Kin Ming () also known as; is a Hong Kongese and Japanese Canadian fashion designer and producing apparel, accessories and fashions for men and women. He is also the founder and the creative director of TATSUAKI fashion label. He was ... {{given name Japanese masculine given names Masculine given names ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eiichiro Fujisaki
Eiichiro, Eiichirō, Eiichirou or Eiichiroh (written: , or ) is a masculine Japanese given name. Notable people with the name include: *Eiichiro Azuma Eiichiro Azuma (born 27 September 1966) is a Japanese-born American historian, writer, and professor. He has served as a Professor of History and Asian American Studies at the University of Pennsylvania. The focus of his work is Japanese America ..., American historian *, Japanese actor and television personality *, Japanese film director *, Japanese folklorist and ethnologist *, Japanese hammer thrower *, Japanese manga artist *, Japanese footballer *, Japanese politician {{given name Japanese masculine given names ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adaptive Chosen Ciphertext Attack
An adaptive chosen-ciphertext attack (abbreviated as CCA2) is an interactive form of chosen-ciphertext attack in which an attacker first sends a number of ciphertexts to be decrypted chosen adaptively, and then uses the results to distinguish a target ciphertext without consulting the oracle on the challenge ciphertext. In an adaptive attack, the attacker is further allowed adaptive queries to be asked after the target is revealed (but the target query is disallowed). It is extending the chosen-ciphertext attack, indifferent (non-adaptive) chosen-ciphertext attack (CCA1) where the second stage of adaptive queries is not allowed. Charles Rackoff and Dan Simon defined CCA2 and suggested a system building on the non-adaptive CCA1 definition and system of Moni Naor and Moti Yung (which was the first treatment of chosen ciphertext attack immunity of public key systems). In certain practical settings, the goal of this attack is to gradually reveal information about an encrypted message ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semantically Secure
In cryptography, a semantically secure cryptosystem is one where only negligible information about the plaintext can be feasibly extracted from the ciphertext. Specifically, any probabilistic, polynomial-time algorithm (PPTA) that is given the ciphertext of a certain message m (taken from any distribution of messages), and the message's length, cannot determine any partial information on the message with probability non-negligibly higher than all other PPTA's that only have access to the message length (and not the ciphertext). S. Goldwasser and S. MicaliProbabilistic encryption & how to play mental poker keeping secret all partial information Annual ACM Symposium on Theory of Computing, 1982. This concept is the computational complexity analogue to Shannon's concept of perfect secrecy. Perfect secrecy means that the ciphertext reveals no information at all about the plaintext, whereas semantic security implies that any information revealed cannot be feasibly extracted. Goldreich ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random Oracle
In cryptography, a random oracle is an oracle (a theoretical black box) that responds to every ''unique query'' with a (truly) random response chosen uniformly from its output domain. If a query is repeated, it responds the same way every time that query is submitted. Stated differently, a random oracle is a mathematical function chosen uniformly at random, that is, a function mapping each possible query to a (fixed) random response from its output domain. Random oracles as a mathematical abstraction were first used in rigorous cryptographic proofs in the 1993 publication by Mihir Bellare and Phillip Rogaway (1993). They are typically used when the proof cannot be carried out using weaker assumptions on the cryptographic hash function. A system that is proven secure when every hash function is replaced by a random oracle is described as being secure in the random oracle model, as opposed to secure in the standard model of cryptography. Applications Random oracles are typicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cipher Space
In cryptography, a cipher (or cypher) is an algorithm for performing encryption or decryption—a series of well-defined steps that can be followed as a procedure. An alternative, less common term is ''encipherment''. To encipher or encode is to convert information into cipher or code. In common parlance, "cipher" is synonymous with " code", as they are both a set of steps that encrypt a message; however, the concepts are distinct in cryptography, especially classical cryptography. Codes generally substitute different length strings of characters in the output, while ciphers generally substitute the same number of characters as are input. There are exceptions and some cipher systems may use slightly more, or fewer, characters when output versus the number that were input. Codes operated by substituting according to a large codebook which linked a random string of characters or numbers to a word or phrase. For example, "UQJHSE" could be the code for "Proceed to the followin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dan Boneh
Dan Boneh (; he, דן בונה) is an Israeli-American professor in applied cryptography and computer security at Stanford University. In 2016, Boneh was elected a member of the National Academy of Engineering for contributions to the theory and practice of cryptography and computer security. Biography Born in Israel in 1969, Boneh obtained his Ph.D. in Computer Science from Princeton University in 1996 under the supervision of Richard J. Lipton. Boneh is one of the principal contributors to the development of pairing-based cryptography, along with Matt Franklin of the University of California, Davis. He joined the faculty of Stanford University in 1997, and became professor of computer science and electrical engineering. He teaches massive open online courses on the online learning platform Coursera. In 1999 he was awarded a fellowship from the David and Lucile Packard Foundation. In 2002, he co-founded a company called Voltage Security with three of his students. The comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
