Basic application to generate the private/public key in order to encrypt and decrypt media. On the basis of these properties ,we can formulate the following reqirements for a digital signature: • The signature must be a bit pattern that depends on the message of being signed. • The signature must use some information uniqe to sender ,to prevent both forgery and denial. • It must be relatively easy to produce the digital signature . • It must be relatively easy to recognize and verify the digital signature. • It must be computationally infeasible to forge a digital signature ,either by constructing a new massage for an existing digital signature or by constructing a fraudulent digital signature for a given message. • It must be practical to return a copy of the digital signature in storage. A secure hash function ,embedded in a scheme such as that of figure satifies these reqirements. THE ALGORITHM: The digital signature algorithm is as follows:
GLOBAL PUBLIC-KEY COMPONENTS:
- p = a prime number, where 2L-1 < p < 2L for 512 = < L = <1024 and L a multiple of 64
- q = a prime divisor of p - 1, where 2159 < q < 2160
- g = h(p-1)/q mod p, where h is any integer with 1 < h < p - 1 such that h(p-1)/q mod P>1 (g has order q mod p) THE USER’S PRIVATE KEY: x = a randomly or pseudorandomly generated integer with 0 < x < q USER’S PUBLIC KEY: y = gx mod p USER’S PER-MESSAGE SECRET NUMBER: k = a randomly or pseudorandomly generated integer with 0 < k < q
The integers p, q, and g can be public and can be common to a group of users. A user's private and public keys are x and y, respectively. They are normally fixed for a period of time. Parameters x and k are used for signature generation only, and must be kept secret. Parameter k must be regenerated for each signature.
TO DEPLOY - 1 - copy the code in netbeans and save it as java 2 - Run the code and cross verify the keys generated.