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Andrew D. Ker


  • University Lecturer in Computer Security, Oxford University Department of Computer Science, 2009-
  • Tutorial Fellow in Computer Science, University College, Oxford, 2009-


  • BA in Mathematics & Computer Science, University College, Oxford, 1994-1997
  • DPhil in Computer Science, University College and Merton College, Oxford, 1997-2000
  • Junior Research Fellow, University College, Oxford, 2000-2003
  • Special Supernumerary Fellow, University College, Oxford, 2003-2009
  • Royal Society University Research Fellow, 2003-2011


I work in information hiding, particularly steganography (hiding secret messages in digital media) and steganalysis (detecting that data has been hidden). You can hear a recording of me talking about my research, in terms suitable for the general public, at the Royal Society in one of their Café Scientifique evenings. My most recent work has been on the mathematical foundations of these disciplines and the "square root law of capacity". I am also interested in digital media forensics. My first research, and doctoral thesis, was on the semantics of programming languages.

Follow this link for my publications.

Graduate Supervision and Internships

I am willing to take on selected students for DPhil (PhD) study: please read this page before approaching me. I also supervise a few internal MSc and undergraduate projects in the department of Computer Science, advertised internally in the usual way. I am not accepting interns at this time.


I am on sabbatical in Michaelmas Term (autumn) 2016 and Hilary Term (spring) 2017.

In the past I have lectured on steganography and steganalysis in a course called Advanced Security, as well as Computer Security, Discrete Mathematics, and Lambda Calculus and Types.

As the tutorial fellow at University College, I am responsible for all undergraduates in Computer Science, Maths & Computer Science, and Computer Science & Philosophy; University College is particularly well-appointed with tutors in these subjects. I teach many of the first and second year Computer Science courses myself, and somtimes probability, statistics, or pure maths. If you are thinking of applying, I recommend reading the Computer Science Department and University College admissions pages.

Selected Professional Activities

Other Interests

I am a musician, specifically a conductor, percussionist, and baritone. I direct a choir that rehearses and performs in University vacations called Intermezzo. I occasionally play percussion in the University Orchestras in Oxford and am somewhat involved in the administration of the Oxford University orchestras. Depending on how industrious they have been recently, you might find up-to-date information on the Oxford University Music Society web site.


My surname is properly pronounced "car".