The Hong Kong University of Science and Technology
Department of Computer Science


PhD Thesis Defence


"Several Constructions of Authentication Codes with Secrecy"

By

Mr. Xiaojian Tian


Abstract

Authentication codes with secrecy are an interesting and important topic
in cryptography. Their constructions can be classified into three
categories: combinatorial, algebraic and geometric. However, the existing
construction methods are mostly combinatorial. Since combinatorial designs
satisfying certain requirements are very rare, the parameters of the
authentication codes based on combinatorial designs are restricted to
certain sets. Thus it is of great value to seek other construction
methods.

In this thesis, we propose a series of construction methods of
authentication codes with secrecy. Two of them are geometric, the others
are algebraic. These constructions are flexible, and can be trimmed to
meet different levels of secrecy and security requirements.  They are also
optimal or asymptotically optimal in the sense that they meet or
asymptotically meet some information-theoretic and combinatorial bounds.


Date:			Monday, 3 May 2004

Time:			1:00p.m.-3:00p.m.

Venue:			Room 2404
			Lifts 17-18

Chairman:		Prof. Ji Shan Hu (MATH)

Committee Members:	Prof. Cunsheng Ding (Supervisor)
			Prof. Mordecai Golin
			Prof. Wai Ho Mow (ELEC)
			Prof. Morris Wang (Elec. & Inf. Engg., PolyU)
			Prof. Chaoping Xing (Math., National Univ. of Singapore)


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