Department of Computer Science, Unit Catalogue 2011/12 

Credits:  6 
Level:  Masters UG & PG (FHEQ level 7) 
Period: 
Semester 2 
Assessment:  CW 25%, EX 75% 
Supplementary Assessment:  Likeforlike reassessment (where allowed by programme regulations) 
Requisites:  Before taking this unit students must have an elementary knowledge of number theory, as in Chapters 12 of Davenport The Higher Arithmetic. 
Description:  Aims: To introduce students to the techniques, tools and pitfalls of cryptography (including authentication etc.). Learning Outcomes: Students will understand the basic mathematics behind privatekey and publickey cryptography. Students will be able to describe and analyse several wellknown techniques for cryptographic security and authentication. Students will be able to evaluate and choose appropriate tools for the application of cryptography in security. Students will have an appreciation of the current state of cryptography research and its issues and future directions. Skills: Analysing and applying techniques for cryptographic security and authentication (T, F, A). Choosing appropriate tools (T, F, A). Content: Introduction to the problem: security, privacy, authentication, repudiation, revocation. The key distribution problem: public vs private keys. The mathematics of crytography: FermatEuler Theorem, structure of finite fields and elliptic curves. Crytographicalgorithms: DiffieHellman, RSAi, ElGamal. Cryptanalysis: discrete logarithms, factoring. The Coppersmith attack. Elliptic Curve analogues. Privatekey algorithms: DES, 3DES and AES. Good hashing algorithms: MD5, SHA1. Characteristics of safe keys, using cryptography: digital signatures: how to find the public key. Repudiation and revocation, examples in practice: PGP, digital certificates. 
Programme availability: 
CM50210 is Compulsory on the following programmes:Department of Computer Science
CM50210 is Optional on the following programmes:Department of Computer Science
