MULTI-S01
Encyclopedia
In cryptography
, MULTI-S01 , is an encryption
algorithm based on a pseudorandom number generator
(PRNG). MULTI-S01 is an encryption scheme preserving both confidentiality
and data integrity
. The scheme defines a pair of algorithms; the encryption, the corresponding decryption with verification
. Coupling with an efficient keystream
generator, such as Panama, MUGI
, and RC4
, the algorithm efficiently encrypts a message in the manner of a single path process, i.e. online algorithm
. The decryption function cannot be used in such manner for keeping whole resultant data until successful verification.
The keysize of MULTI-S01 is determined by which keystream generator to use. MULTI-S01 takes a security parameter which determines the upperbound probability of successful forgery.
Since the calculation consists of addition and multiplication over the finite field
, the algorithm is more suited to hardware implementation, although software implementation is still feasible.
MULTI-S01 with the PRNG Panama has been selected as one of CRYPTREC
algorithms. It has also been submitted to ISO/IEC
18033 Part 4 which defines stream-cipher standards.
The security of MULTI-S01 is based on that of underlying PRNG. If a secure PRNG is used, then the security of MULTI-S01 with respect to confidentiality and data integrity has been proven. As for the data integrity, the security proof is basically the same as one for Carter–Wegman MAC scheme, which is proven to be information-theoretically secure.
Cryptography
Cryptography is the practice and study of techniques for secure communication in the presence of third parties...
, MULTI-S01 , is an encryption
Encryption
In cryptography, encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information...
algorithm based on a pseudorandom number generator
Pseudorandom number generator
A pseudorandom number generator , also known as a deterministic random bit generator , is an algorithm for generating a sequence of numbers that approximates the properties of random numbers...
(PRNG). MULTI-S01 is an encryption scheme preserving both confidentiality
Confidentiality
Confidentiality is an ethical principle associated with several professions . In ethics, and in law and alternative forms of legal resolution such as mediation, some types of communication between a person and one of these professionals are "privileged" and may not be discussed or divulged to...
and data integrity
Data integrity
Data Integrity in its broadest meaning refers to the trustworthiness of system resources over their entire life cycle. In more analytic terms, it is "the representational faithfulness of information to the true state of the object that the information represents, where representational faithfulness...
. The scheme defines a pair of algorithms; the encryption, the corresponding decryption with verification
Verification
The word verification may refer to:* Verification and validation, in engineering or quality management systems, it is the act of reviewing, inspecting or testing, in order to establish and document that a product, service or system meets regulatory or technical standards.* Verification , in the...
. Coupling with an efficient keystream
Keystream
In cryptography, a keystream is a stream of random or pseudorandom characters that are combined with a plaintext message to produce an encrypted message ....
generator, such as Panama, MUGI
MUGI
In cryptography, MUGI is a pseudorandom number generator designed for use as a stream cipher. It has been recommended for Japanese government use by the CRYPTREC project.MUGI takes a 128-bit secret key and a 128-bit initial vector...
, and RC4
RC4
In cryptography, RC4 is the most widely used software stream cipher and is used in popular protocols such as Secure Sockets Layer and WEP...
, the algorithm efficiently encrypts a message in the manner of a single path process, i.e. online algorithm
Online algorithm
In computer science, an online algorithm is one that can process its input piece-by-piece in a serial fashion, i.e., in the order that the input is fed to the algorithm, without having the entire input available from the start. In contrast, an offline algorithm is given the whole problem data from...
. The decryption function cannot be used in such manner for keeping whole resultant data until successful verification.
The keysize of MULTI-S01 is determined by which keystream generator to use. MULTI-S01 takes a security parameter which determines the upperbound probability of successful forgery.
Since the calculation consists of addition and multiplication over the finite field
Finite field
In abstract algebra, a finite field or Galois field is a field that contains a finite number of elements. Finite fields are important in number theory, algebraic geometry, Galois theory, cryptography, and coding theory...
, the algorithm is more suited to hardware implementation, although software implementation is still feasible.
MULTI-S01 with the PRNG Panama has been selected as one of CRYPTREC
CRYPTREC
CRYPTREC is the Cryptography Research and Evaluation Committees set up by the Japanese Government to evaluate and recommend cryptographic techniques for government and industrial use...
algorithms. It has also been submitted to ISO/IEC
International Electrotechnical Commission
The International Electrotechnical Commission is a non-profit, non-governmental international standards organization that prepares and publishes International Standards for all electrical, electronic and related technologies – collectively known as "electrotechnology"...
18033 Part 4 which defines stream-cipher standards.
The security of MULTI-S01 is based on that of underlying PRNG. If a secure PRNG is used, then the security of MULTI-S01 with respect to confidentiality and data integrity has been proven. As for the data integrity, the security proof is basically the same as one for Carter–Wegman MAC scheme, which is proven to be information-theoretically secure.