## MA115-Codes and Code Breaking

Module Provider: Mathematics and Statistics
Number of credits: 20 [10 ECTS credits]
Level:4
Terms in which taught: Autumn / Spring / Summer module
Pre-requisites:
Non-modular pre-requisites: GCSE Mathematics grade B
Co-requisites:
Modules excluded:
Current from: 2018/9

Module Convenor: Dr Basil Corbas

Type of module:

Summary module description:
To introduce contemporary methods for the secure transmission of data and messages and justify the need for such new methods by analysing the shortcomings of traditional techniques. To illustrate how simple mathematical ideas can be used to solve practical problems in a context very different from the ones which mathematics are traditionally associated with.

Aims:
To introduce contemporary methods for the secure transmission of data and messages and justify the need for such new methods by analysing the shortcomings of traditional techniques. To illustrate how simple mathematical ideas can be used to solve practical problems in a context very different from the ones which mathematics are traditionally associated with.

Assessable learning outcomes:

By the end of the module students are expected to be able to:

• break simple codes;

• encipher and decipher using traditional methods as well as public key cryptosystems like the RSA;

• apply a digital signature;

• authenticate a digital signature.

At the end of the course students will have acquired some familiarity and confidence to use numbers in order to solve some practical problems in a fascinating and unexpected way.

Outline content:
The course begins with an introduction to the traditional methods of cryptography and proceeds to demonstrate their weaknesses by examining methods of breaking those codes.
It then considers how these reasons together with the proliferation of the transmission of sensitive data in the 1970's led searchers to seek totally different methods for the secret transmission of messages.
These new methods are based on properties of numbers that are fascinating and at the same time can be understood with remarkably little effort. The course will essentially build from scratch these numerical prerequisites.
The new style of cryptography is ingenious because it permits each person who is to receive secret information to publicly tell how to scramble messages sent to him or her. But in addition it solves seemingly non solvable problems such as how does one sign digitally a document, or how can one check that a digital message was not sent by an impostor, or that the data included in a digital document has not been maliciously altered?

Brief description of teaching and learning methods:
Lectures supported by problem sheets

Contact hours:
 Autumn Spring Summer Lectures 20 20 4 Guided independent study 78 78 Total hours by term 98.00 98.00 4.00 Total hours for module 200.00

Summative Assessment Methods:
 Method Percentage Written exam 80 Set exercise 20

Summative assessment- Examinations:
3 hours.

Summative assessment- Coursework and in-class tests:
Two assignments and one examination paper.

Formative assessment methods:
Problem sheets.

Penalties for late submission:
The Module Convener will apply the following penalties for work submitted late:

• where the piece of work is submitted after the original deadline (or any formally agreed extension to the deadline): 10% of the total marks available for that piece of work will be deducted from the mark for each working day[1] (or part thereof) following the deadline up to a total of five working days;
• where the piece of work is submitted more than five working days after the original deadline (or any formally agreed extension to the deadline): a mark of zero will be recorded.

• The University policy statement on penalties for late submission can be found at: http://www.reading.ac.uk/web/FILES/qualitysupport/penaltiesforlatesubmission.pdf
You are strongly advised to ensure that coursework is submitted by the relevant deadline. You should note that it is advisable to submit work in an unfinished state rather than to fail to submit any work.

Assessment requirements for a pass:
A mark of 40% overall.

Reassessment arrangements:
One examination paper of 3 hours duration in August/September - the resit module mark will be the higher of the exam mark (100% exam) and the exam mark plus previous coursework marks (80% exam, 20% coursework).