## About

5

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12

Citations

Citations since 2016

## Publications

Publications (5)

As many vulnerabilities of one-time authentication systems have already been uncovered, there is a growing need and trend to adopt continuous authentication systems. Biometrics provides an excellent means for periodic verification of the authenticated users without breaking the continuity of a session. Nevertheless, as attacks to computing systems...

A large class of biometric template protection algorithms assume that feature vectors are integer valued. However, biometric data is generally represented through real-valued feature vectors. Therefore, secure template constructions are not immediately applicable when feature vectors are composed of real numbers. We propose a generic transformation...

We present faster algorithms for the residue multiplication modulo 521-bit Mersenne prime on 32- and 64-bit platforms by using Toeplitz matrix-vector product. The total arithmetic cost of our proposed algorithms is less than that of existing algorithms, with algorithms for 64- and 32-bit residue multiplication giving the best timing results on our...

We present a new algorithm for residue multiplication modulo the Mersenne prime \(p=2^{521}-1\) based on the Toeplitz matrix-vector product. For this modulus, our algorithm yields better result in terms of the total number of operations than the previously known best algorithm of Granger and Scott presented in Public Key Cryptography (PKC) 2015. We...

## Questions

Questions (10)

Bernstein et. al. in their paper, Curve41417 (Karatsuba Revisited), have specified that they are using signed fixed window width of size 5. But in the section 4, where the algorithm is described, they are counting the number of operations without specifying any use of window method.

Where are they using the signed fixed window method? Definitely, I have missed something.

Assume we have two n-bit integers a, b so the cost(a+b) = n-bit operations. Similarly, the cost of adding two 2n-bit integers will be 2n-bit operations. This is how we compute the cost of operation in theory.

Is it also true in practice? I mean may be the hardware engineers optimize the operation for large integers so that to speedup the performance of the machine.

1)Asymptotically the cost of finite field multiplication is same as field squaring. How to measure their ratio accurately on a machine?

2)Similarly, the asymptotic cost of finite field multiplication is same as field inversion. So how to measure their ratio accurately on a machine?

We use reduction to solve problem P1 using problem P2 such that a solution of P2 is also a solution of P1.

While a problem P1 is transformed into a simpler form so that solving P1 becomes easy.

So the solution set is same in both cases.

I think we prefer Public-key Cryptography, because of its computationally hardness, over Private-key Cryptography. Is this the only reason or?

Suppose we are considering only confidentiality and for now just ignoring the active attacks. So we encrypt the email with the secret key generated by online trusted third party and then send both the ticket and encrypted email to the receiver. By ignoring the problems and drawbacks of the online trusted third party. So what are the problems with this mechanism? Also for each email/session we are using a new key.

## Projects

Project (1)

Securing biometrics, Physiological and Behavioral biometrics, Noise Tolerant Templates, Efficient implementation etc.