This presentation gives the detail information about the error handling methods used in bio-cryptography. and also tells about bio - cryptography.

1. Seminar On
Error Handling Methods Used in
Bio-Cryptography
Presented by: Kanchan P. Nawkar (18)
Guided By: Prof. A. K. Shahade

2. Contents
1. Introduction to Biometrics
I. Biometrics Processing
II. Biometrics errors
III. Performance Of Biometrics
2. Introduction To Cryptography
I. Processing Of Cryptography
3. Problem statement
4. Error Handling Methods
I. Quantization
II. Subsetting
III. Error correction Coding
5. Conclusion

3. 1. Introduction To Biometrics:
Biometrics refers to the automatic identification of a person based on
his or her physiological or behavioral characteristics .

4. 1.1 Biometrics Processing:

5. 1.3 Performance Of Biometrics:
• False acceptance rate (FAR)
• False recognition rate (FRR)
1.2 Biometric devices can make two kinds of errors:
• The false accept
• The false reject

6. 2.Introduction To Cryptography:
• Cryptography is an important feature of computer security. It is
dependent on the private key.
• The user chooses an easily remembered pass code that is used to
encrypt the cryptographic key and this key is then stored in a
database.
• Security of the cryptographic key is weak due to practical
problems of remembering pass codes.

7. 2.1 Processing Of Cryptography:
There are various types of algorithms for encryption, some common
algorithms include:
• Secret Key Cryptography (SKC)
• Public Key Cryptography (PKC)
• Hash Functions

8. 3. Problem Statement:
Biometric system works with two steps:
• Registration: For registration a person provide a live biometric for
measurements and the results will be stored.
• Verification: For verification, the person must provide the same
biometric for new measurements.
The output of the new measurements will be compared to the previously
stored results. Biometric measurements generate noisy data and it is a
challenging problem to achieve security with noisy data .
So, to solve the problem of noisy data combine the cryptographic key
with Biometrics.

9. • A few biometrics, including keystroke dynamics, voice,
handwritten signatures, face, iris, and fingerprint, have been
proposed for cryptographic key binding.
• For different biometrics, different techniques have to be chosen to
solve the fuzzy measurement problems. Biometrics-exemplified
error tolerance techniques are as follows:
1. Quantization
2. Subsetting
3. Error correction Coding
4. Error Handling Methods:

10. 4.1 Quantization
• Individual biometric image will be quantized into a number of small units.
• Delaunay Triangulation is used to generate feature vector, for each minutiae
mi the set of triangles shares the vertex mi. This is denoted as local structure
centered on mi, TSi.
• To tolerate the deformation each segment of feature vector is quantized.

11. • The matching between a saved template and a query is being done on the
transformed domain by considering number of matched triangles in each
local structure.
• In this method error tolerance is handled by quantization as well as the
properties of Delaunay triangles.
4.2 Subsetting:
Fuzzy Vault Scheme
• Fuzzy vault is a bio-cryptographic construction.
• The security of this method depends completely upon the polynomial
reconstruction problem.

12. •Let, consider a secret K, during vault construction it is encoded into
coefficients of a polynomial P of degree D
•Then improved the method by introducing CRC (Cyclic Redundancy
Check) in the polynomial..
•CRC: A code added to data which is used to detect errors occurring
during transmission, storage, or retrieval.

13. 4.3 Error Correction Codes (ECCs):
Overviews of ECCs used in Bio-Cryptography are as follows:
• Reed Solomon:
RS codes are a set of algebraic codes which are used for error
correction at block level. Let, consider m blocks of information [x1, x2,..., xm]
and during encoding these blocks are embedded in coefficients of a polynomial
P of degree (m−1).
P(y) = x m y(m−1) + x(m−1)y(m−2) + ... +1 -------(1)
Then, it is possible to generate n codewords from P(y) by substituting values
y € Z. From a corrupted codeword, RS decoding can reconstruct the original
polynomial given that n = m+2t.
Afterwards, by extracting the coefficients of the reconstructed polynomial, the
original message can be unravelled.

14. • Hadamard Codes:
Hadamard codes are constructed from the Hadamard matrix which is
a square matrix with elements 1 or−1. If Hc(k) and H(k) denote a set of
Hadamard codes and a Hadamard matrix; then,
Hc
(k)= (H(k)
-H(k))
Therefore, if we consider a Hadamard code of size n =2k bits, then there are 2n
codewords generated in total. Furthermore, the code is having a minimum
distance of 2k−1 which suggests that it can correct up to 2k−2 -1 error.

15. Conclusion:
• Biometric Encryption and Bios-crypt are high security means of protecting
the critical data of government, police departments, army and big firms.
• The current generation of biometric identification devices offer cost and
performance advantages over manual security procedures.
• All these methods have shown that, using biometrics for identification or
verification-based security systems and cryptosystems, is a promising
technology