NEW SECTION:

SECTION ID: COMP6211

This section contains questions pertaining to the material taught in

COMP6211 – Biometrics

This section contains 2 questions with the following QUESTION IDs:

COMP6211_1

COMP6211_2

Answer ALL questions

In your record of the answers, remember to record the CFA ID, the

SECTION ID, the QUESTION ID and YOUR ID at the top of EVERY

page and include a page number for your answers to assist in ordering.

Once you have completed the answers, produce and save an individual

PDF file for the answers to THIS SECTION ONLY.

To upload your file, follow the instructions at the start of this document.

Question COMP6211_1

It has been suggested that signals from the cardiovascular system can

be used in biometric authentication. The signals of particular interest

here derive from photoplethysmography (PPG), which refers to the use

of illumination-based sensors that are sensitive to volumetric changes as

blood travels through the body. Photoplethysmography sensors have

been developed for the fingertip and the ear lobe, and can provide a

convenient, noninvasive means of measuring heart rate and heart-rate

variability. Figure (Q1) shows Photoplethysmography signals from three

different subjects, obtained using a fingertip pulse oximeter. Different

individuals can exhibit significant differences in PPG signal morphology,

and these differences can be exploited for biometric authentication.

Figure (Q1) Photoplethysmography signals

[Sarkar, Abbott and Lynn, Proc. IEEE BTAS 2016]

Describe basic considerations of the nature of these signals and how

they could be used as a basis for a biometric system. Describe how the

signals could be transformed into feature vectors suitable for recognition,

and the process that would use these feature vectors for authentication

purposes.

[50 marks]

Question COMP6211_2

(a) Biometric authentication is largely based on interpreting measures

of distance. Describe how these distance measures can be

deployed to recognise or to authenticate people.

[15 marks]

(b) For sets of vector points = (1 ,2 ,3 , … ,) which have

mean values = (1, 2, 3,… , ) and covariance matrix Σ, the

Mahalanobis distance measure is defined as:

= √( − )Σ−1( − )

where the covariance matrix is formed of elements which express

the variance as

Σ = [( − )( − )]

where denotes the expected value.

For a system where there are three classes whose two

dimensional feature vectors are arranged with mean values (1,1),

(10,10) and (5,5) with variances (0.1,0.1), (1,1) and (2,2),

respectively, describe the possible result of recognition using the

Mahalanobis distance measure compared with than achieved

using the Euclidean distance.

[23 marks]

(c) Describe approaches that can be used to augment performance

when recognition within a biometric modality does not appear able

to achieve recognition.

[12 marks]

NEW SECTION:

SECTION ID: COMP6239

This section contains questions pertaining to the material taught in

COMP6239 – Mobile Applications Development

This section contains 2 questions with the following QUESTION IDs:

COMP6239_1

COMP6239_2

Answer ALL questions

In your record of the answers, remember to record the CFA ID, the

SECTION ID, the QUESTION ID and YOUR ID at the top of EVERY

page and include a page number for your answers to assist in ordering.

Once you have completed the answers, produce and save an individual

PDF file for the answers to THIS SECTION ONLY.

Follow the instructions on the rubric at the front of this document for

uploading.

Question COMP6239_1

Explain the various scenarios, based on different business needs that

you may face, and the kinds of development approaches you may

choose for your team to undertake. You are required to devise at least

four different scenarios. For each suggested development approach,

justify their suitability and consequences in terms of potential

advantages and disadvantages.

Hint: You can refer to lectures explaining the four different approaches to

mobile app development and the different reasons that a business may

require a mobile application.

[50 marks]

Question COMP6239_2

As part of the transformation to modern Android Apps, Google has

recently released Android Jetpack - a modern suite of architecture

guidelines, tools and libraries. Name the major components of this

modern suite and in each case briefly explain, in your view, the type of

effects it may have on the future of Android mobile applications.

[50 marks]

NEW SECTION:

SECTION ID: ELEC6242

This section contains questions pertaining to the material taught in

ELEC6242 – Cryptography

This section contains 2 questions with the following QUESTION IDs:

ELEC6242_1

ELEC6242_2

Answer ALL questions

In your record of the answers, remember to record the CFA ID, the

SECTION ID, the QUESTION ID and YOUR ID at the top of EVERY

page and include a page number for your answers to assist in ordering.

Once you have completed the answers, produce and save an individual

PDF file for the answers to THIS SECTION ONLY.

To upload your file, follow the instructions at the start of this document.

Question ELEC6242_1

(a) Explain the meaning of “Kirchhoff's Principle” and its relevance to

the design of modern ciphers.

[10 marks]

(b) Outline the principles of the cipher block chaining (CBC) mode of

operation, and explain the reasons behind its use.

[10 marks]

(c) Compression methods are typically used to prevent the use of data

redundancy in cryptanalysis. Calculate the theoretical maximum

compression ratio which can be achieved for the following

message (M2):

M2 = 1001111111

[10 marks]

(d) Steve has managed to intercept two of Bob‘s messages to Alice

(m1=33121, m2=16879) with their respective RSA digital

signatures (s1=42813, s2=39667). Explain with numerical

examples two methods that Steve may use to forge Bob’s

signature. It is assumed that the following parameters of the RSA

digital signature scheme used are known to Steve:

RSA modulus N=49163

The exponent of e=151

[20 marks]

Question ELEC6242_2

Let be the elliptic curve 2 = 3 + + 7 over the field F13=Z13

We regard as an Abelian group in the usual way.

(a) Explain the meaning of “group order” in number theory, then find

the order of the above group and indicate whether or not this is a

cyclic group.

[10 marks]

(b) Find an integer ≥ 0 such that

(11,6) = (2, 2) in

and explain your working in details

[10 marks]

(c) Find all pairs of points (P, Q) such that:

P + Q = 0

and explain your working in detail.

[10 marks]

(d) Alice has received the encrypted message {C1, C2} from Bob,

where:

C1= (2,2)

C2= 5

Explain in detail how to decrypt Alice’s message, assuming the

Elgamal encryption algorithm with the above group () was used to

encrypt it.

You are also given the following information

The generator point: G= (11,6)

Alice’s secret key: a=2

[20 marks]