Mathematical Problems in Engineering / 2013 / Article / Tab 5

Research Article

Cryptanalysis and Performance Evaluation of Enhanced Threshold Proxy Signature Scheme Based on RSA for Known Signers

Table 5

The commonly supported and used algorithms used in protocol.

Diffie-Hellman key exchange algorithmFirst published public key algorithm,
can be used only for exchanging keys
Uses recipient’s public key to generate a secret key; public data is then sent to recipient who can now generate the secret key

(digital signature algorithm)
Does not encrypt data, but produces a signature that can be verified
A public key (of 3 parts) is calculated from a private key
Signing: input is data to be signed, private key, a random number; output is a signature, comprising 2 numbers called r & s
Verifying: input is data to be verified, public key & s; output is a number called v; if v = r then signature is verified

(secure hash algorithm)
US government standard produced by NIST
Based on MD4 algorithm. Revised version of 1995 called SHA-1
Takes a message of less than 264 bits and produces a message digest/fingerprint of 160 bits

(digital signature standard)
US government standard methodUses DSA to sign a message digest/fingerprint produced by SHA

(T ElGamal’s algorithm)
Variant of Diffie-Hellman for encryption and decryption as well as key exchangesSometimes known as Diffie-Hellman in earlier versions of PGP

(Rivest-Shamir-Adleman algorithm)
First main, and still, the most widely used general purpose public-key encryption algorithmEncrypt message with public key to obtain confidentiality
Encrypt message with private key to obtain authentication, integrity, and nonrepudiation

triple DES (data enrcyption standard)
DES was the first widespread symmetric key encryption algorithm
3DES applies the algorithm 3 times for additional security
DES is a 56-bit key, 64-bit block cypher using multiple rounds of permutations and substitutions
Now considered necessary to apply 3 times with 3 keys

(developed by Carlisle Adams and Stafford Tavares)
Modern symmetric key encryption algorithm
CAST-128 is an implementation of the CAST design procedure
Uses key sizes of 40 to 128 bits (in 8-bit increments) with 16 rounds of 64-bit blocks of plaintext
Has been extensively reviewed by cryptologists

(international data encryption algorithm)
Modern symmetric key encryption algorithm, designed as a replacement for DES128-bit key block cypher encrypting 64-bit blocks of plaintext

(Daemen and Rijmen’s algorithm)
Selected for the new “Advanced Encryption Standard” by NIST to replace DESHigh performance and very secure algorithm, using key sizes of 128, 192, and 256 bits

RSASelected for the new “Advanced Encryption Standard” by NISTHigh performance and very secure algorithm