08-08-2012, 01:27 PM
A New Forward-Secure Digital Signature Scheme
[attachment=30566]
Objective
ECDSA is advanced, and a new forward-secure digital signature scheme is proposed in order to reform the limitations of ECDSA digital signature’s private key is under the control of a one-way function and continually changed in different durations with time goes by, its public key remains the same.
System Analysis
EXISTING SYSTEM
The disadvantage to RSA is speed.
Prime factorization in DSA requires splitting an integer into factors that are prime numbers; every integer has a unique prime factorization.
Proposed system
The biggest advantage to public-key cryptography is the individuals do not need to agree on a single key.
EC operations are generally faster than DL, IF counterparts at comparable key sizes. Key pair generation is much faster.
EC data are shorter than DL, IF counterparts. Intermediate values are shorter. Signatures with appendix are same size as for DL, shorter than IF.
Elliptic Curve Digital Signature Algorithm (ECDSA)
Entity A has domain parameters D = (q, a, b, G, n, h) and public key QA and private key dA. And entity B has authentic copies of D and QA.
To sign a message m, A does the following:
Select a random integer k from [1,n-1].
Compute kG = (x1,y1) and r = x1 mod n. If r = 0 then go to step 1.
Compute k-1 mod n. Compute e = SHA-1(m).
Compute s = k-1{e + dA . r} mod n.
If s = 0 then go to step 1.
A's signature for the message m is (r, s).
To verify A's signature (r, s) on m, B performs the following steps:
Verify that r and s are integers in [1,n-1].
Compute e = SHA-1(m).
Compute w = s-1 mod n.
Compute u1 = ew mod n and u2 = rw mod n.
Compute (x1,y1) = u1G+ u2 QA
Compute v = x1 mod n.
Accept the signature if and only if v = r.
SHA-1 denotes the 160-bit hash function
Modules
We propose the following modules:
Process of generating the first key pair signatory.
Signature procedure and Verification procedure.
Check validity using Time Factor.
Process of generating the first key pair signatory:
Choosing a random curve from given number of curves for getting random point.
In this point value is used to generate a private and public key pairs. Here the private key will be maintained secrete manner but the public key will be send to receiver end.
Signature procedure and Verification procedure:
Signature will be generate upon already generated private key and message.
When our private key or message will be changing automatically signature also changed.
Signature procedure will be done on sender side.
Verification procedure will be done on receiver end.
Check validity using Time Factor :
While sending message the sender will set the time limit for the signature.
Receiver end verifies the signature and decrypt the message with in time limit.
Suppose the time limit will exceed,the receiver will not be able to decrypt the message using previous signature.
Now receiver send request for new signature to sender side.
Data flow diagrams
Context Level Diagram:
DFD for Login:
DFD for Key Generation:
DFD for Generating Signature:
DFD for Verifying Signature:
[attachment=30566]
Objective
ECDSA is advanced, and a new forward-secure digital signature scheme is proposed in order to reform the limitations of ECDSA digital signature’s private key is under the control of a one-way function and continually changed in different durations with time goes by, its public key remains the same.
System Analysis
EXISTING SYSTEM
The disadvantage to RSA is speed.
Prime factorization in DSA requires splitting an integer into factors that are prime numbers; every integer has a unique prime factorization.
Proposed system
The biggest advantage to public-key cryptography is the individuals do not need to agree on a single key.
EC operations are generally faster than DL, IF counterparts at comparable key sizes. Key pair generation is much faster.
EC data are shorter than DL, IF counterparts. Intermediate values are shorter. Signatures with appendix are same size as for DL, shorter than IF.
Elliptic Curve Digital Signature Algorithm (ECDSA)
Entity A has domain parameters D = (q, a, b, G, n, h) and public key QA and private key dA. And entity B has authentic copies of D and QA.
To sign a message m, A does the following:
Select a random integer k from [1,n-1].
Compute kG = (x1,y1) and r = x1 mod n. If r = 0 then go to step 1.
Compute k-1 mod n. Compute e = SHA-1(m).
Compute s = k-1{e + dA . r} mod n.
If s = 0 then go to step 1.
A's signature for the message m is (r, s).
To verify A's signature (r, s) on m, B performs the following steps:
Verify that r and s are integers in [1,n-1].
Compute e = SHA-1(m).
Compute w = s-1 mod n.
Compute u1 = ew mod n and u2 = rw mod n.
Compute (x1,y1) = u1G+ u2 QA
Compute v = x1 mod n.
Accept the signature if and only if v = r.
SHA-1 denotes the 160-bit hash function
Modules
We propose the following modules:
Process of generating the first key pair signatory.
Signature procedure and Verification procedure.
Check validity using Time Factor.
Process of generating the first key pair signatory:
Choosing a random curve from given number of curves for getting random point.
In this point value is used to generate a private and public key pairs. Here the private key will be maintained secrete manner but the public key will be send to receiver end.
Signature procedure and Verification procedure:
Signature will be generate upon already generated private key and message.
When our private key or message will be changing automatically signature also changed.
Signature procedure will be done on sender side.
Verification procedure will be done on receiver end.
Check validity using Time Factor :
While sending message the sender will set the time limit for the signature.
Receiver end verifies the signature and decrypt the message with in time limit.
Suppose the time limit will exceed,the receiver will not be able to decrypt the message using previous signature.
Now receiver send request for new signature to sender side.
Data flow diagrams
Context Level Diagram:
DFD for Login:
DFD for Key Generation:
DFD for Generating Signature:
DFD for Verifying Signature: