Dr Rachel Player

Lecturer in Information Security

About Me

Hi! My name is Dr Rachel Player and I’m a lecturer in the Department of Information Security at Royal Holloway, University of London and a visiting researcher at The Alan Turing Institute. In January - May 2019, I was a visiting researcher in the PolSys team of LIP6 at Sorbonne Université in Paris, having previously held a postdoctoral position in the same team. I obtained my PhD from Royal Holloway in 2018.

My main research interests are post-quantum cryptography, especially lattice-based cryptography, and homomorphic encryption. I am also interested in the application of quantum algorithms in cryptanalysis. In 2019 I was honoured by Internet Security Research Group with The Radiant Award for Advancing Internet Security.

I am fortunate to work with the following PhD students: Erin Hales, Tabitha Ogilvie and postdocs: Benjamin R. Curtis, Daniel Gardham. I have previously been fortunate to work with: Anamaria Costache (now Associate Professor at NTNU).

In the 2020-21 academic year, I am the module leader of IY3501 Security Management and I supervise BSc and MSc projects in Information Security.

Publications

Discretisation and Product Distributions in Ring-LWE

Sean Murphy, Rachel Player. Journal of Mathematical Cryptology. Volume 15, Issue 1, Pages 45–59, 2021.

Improved privacy-preserving training using fixed-Hessian minimisation

Tabitha Ogilvie, Rachel Player, Joe Rowell. WAHC 2020 – 8th Workshop on Encrypted Computing & Applied Homomorphic Cryptography, to appear.

Evaluating the effectiveness of heuristic worst-case noise analysis in FHE

Anamaria Costache, Kim Laine, Rachel Player. 25th European Symposium on Research in Computer Security, ESORICS 2020, Proceedings, Part II, pp. 546-565.

On the Feasibility and Impact of Standardising Sparse-secret LWE Parameter Sets for Homomorphic Encryption

Benjamin R. Curtis, Rachel Player. 7th Workshop on Encrypted Computing & Applied Homomorphic Cryptography, WAHC@CCS 2019, pages 1-10, 2019.

A Central Limit Framework for Ring-LWE Decryption

Sean Murphy, Rachel Player. Preprint.

Achieving secure and efficient lattice-based public-key encryption: the impact of the secret-key distribution

Sauvik Bhattacharya, Oscar Garcia-Morchon, Rachel Player, Ludo Tolhuizen. Preprint.

δ-subgaussian random variables in cryptography

Sean Murphy, Rachel Player. 24th Australasian Conference on Information Security and Privacy, ACISP 2019, Proceedings, pages 251-268, 2019.

Estimate all the {LWE,NTRU} schemes!

Martin R. Albrecht, Benjamin R. Curtis, Amit Deo, Alex Davidson, Rachel Player, Eamonn W. Postlethwaite, Fernando Virdia, Thomas Wunderer. Security and Cryptography for Networks - 11th International Conference, SCN 2018, Proceedings, pages 351-367, 2018. Check out the project webpage.

High-Precision Arithmetic in Homomorphic Encryption

Hao Chen, Kim Laine, Rachel Player, Yuhou Xia. Topics in Cryptology – CT-RSA 2018, Proceedings, pages 116–136, 2018.

Simple Encrypted Arithmetic Library – SEAL v2.1

Hao Chen, Kim Laine, Rachel Player. Financial Cryptography and Data Security – FC 2017 International Workshops, WAHC, BITCOIN, VOTING, WTSC, and TA, Revised Selected Papers, pages 3–18, 2017.

On the Hardness of LWE with Binary Error - Revisiting the Hybrid Lattice-Reduction and Meet-in-the-Middle Attack

Johannes Buchmann, Florian Göpfert, Rachel Player, Thomas Wunderer. Progress in Cryptology – AFRICACRYPT 2016, pages 24–43, 2016.

On the concrete hardness of Learning with Errors

Martin R. Albrecht, Rachel Player, Sam Scott Journal of Mathematical Cryptology. Volume 9, Issue 3, Pages 169–203, 2015. Check out the LWE Estimator or its documentation.

Talks

  • 25 January 2021. Homomorphic encryption: An introduction. The Alan Turing Institute, Defence & Security Monthly Meetup, Virtual
  • 14 December 2020. Homomorphic encryption: Recent results and next steps. ACE CSR Winter School, Virtual
  • 14 July 2020. Security and noise growth in homomorphic encryption. MSR Cryptography Colloquium, Virtual
  • 7 February 2020. Security and noise growth in HE: Recent results and next steps. Homomorphic Encryption Standardization Strategic Planning Meeting, Microsoft Research, Redmond, USA
  • 16 December 2019. Homomorphic noise growth in practice. IMA International Conference on Cryptography and Coding, Oxford, UK
  • 6 December 2019. Evaluating the effectiveness of heuristic worst-case noise analysis in FHE. DS Lunch Colloquium, Radboud University, Nijmegen
  • 2 December 2019. Evaluating the effectiveness of heuristic worst-case noise analysis in FHE. COSIC Seminar, KU Leuven, Belgium
  • 18 October 2019. On the condition number of Macaulay matrices. Dagstuhl Seminar on Quantum Cryptanalysis, Germany
  • 18 August 2019. Discretisation and Product Distributions in Ring-LWE. MathCrypt 2019 workshop presentation, Santa Barbara, USA
  • 3 July 2019. δ-subgaussian Random Variables in Cryptography. ACISP 2019 conference presentation, Christchurch, New Zealand
  • 2 May 2019. δ-subgaussian Random Variables in Cryptography. PROMETHEUS meeting, CWI, Amsterdam
  • 26 February 2019. Homomorphic Encryption: State of the art and applications. Invited seminar at Cryptosense, Paris, France
  • 10 August 2018. Security and encoding in Fully Homomorphic Encryption. Seminar at the Turing, Turing Institute, London, UK
  • 18 July 2018. Homomorphic Encryption: State of the art and applications. Invited talk at Workshop on Privacy Enhancing Technologies, Royal Society, London, UK
  • 18 April 2018. High-Precision Arithmetic in Homomorphic Encryption. CT-RSA Conference presentation, San Francisco, USA
  • 12 April 2018. Estimate all the {LWE,NTRU} schemes!. Invited talk at First PQC standardization conference, Fort Lauderdale, USA
  • 9 March 2018. Estimate all the {LWE,NTRU} schemes!. Quantum-safe cryptography seminar, Sorbonne Université, Paris, France
  • 29 September 2017. Parameter selection in Ring-LWE-based FHE. Lattice coding & crypto meeting, Imperial College, London, UK
  • 21 April 2017. Parameter selection for security and correctness in FHE. Microsoft Research, Redmond, USA
  • 7 April 2017. Simple Encrypted Arithmetic Library – SEAL. WAHC’17 conference presentation, Sliema, Malta
  • 2 February 2017. Simple Encrypted Arithmetic Library – SEAL. PhD Student Seminar, Royal Holloway, University of London, UK
  • 7 September 2016. Simple Encrypted Arithmetic Library – SEAL. Workshop on lattice-based cryptography with Kyushu University, Royal Holloway, University of London, UK
  • June 2016. On the concrete hardness of Learning with Errors. Crypto group lunch, Microsoft Research, Redmond, USA
  • 29 February 2016. On the hardness of LWE with binary error. Workshop on cyber security, Kyushu University, Japan
  • 4 November 2015. On the concrete hardness of Learning with Errors. Cryptography seminar, University of Oxford, UK
  • 25 May 2015. On the concrete hardness of Learning with Errors. Presentation at ICMS Workshop, Edinburgh, UK
  • 26 March 2015. On the concrete hardness of Learning with Errors. CROSSING student seminar, TU Darmstadt, Germany
  • 12 March 2015. On the concrete hardness of Learning with Errors. ISG Seminar, jointly with Sam Scott, Royal Holloway, University of London, UK
  • 20 February 2015. On the concrete hardness of Learning with Errors. Cryptography group seminar, University of Bristol, UK

Experience

Department of Information Security, Royal Holloway, UK

Novemer 2019 - present

Lecturer

I am a lecturer in the Department of Information Security. For my latest research results, see my dblp and Google Scholar entries.

Service:

ISG, Royal Holloway, UK

January 2019 - October 2019

Postdoctoral researcher

I was a postdoc in the Information Security Group working with Martin R. Albrecht as part of the EU H2020 PROMETHEUS project on lattice-based cryptography.

LIP6, Paris, France

February 2018 - December 2018

Postdoctoral researcher

I was a postdoc in the PolSys group of LIP6 which is common between Sorbonne Université, CNRS and INRIA. I worked with Jean-Charles Faugère and Ludovic Perret on post-quantum cryptography as part of the RISQ project.

Microsoft Research, Redmond, USA

April - July 2016

Intern

I interned in the Cryptography Group where my mentor was Kim Laine. The goal of my internship was to implement the FV scheme in Microsoft SEAL. In June 2016, we released this as SEAL v2.0.

Education

Royal Holloway, University of London

2013 - 2018

Information Security (PhD)

I studied for my PhD in the Information Security Group where I was supervised by Carlos Cid and Sean Murphy. A major focus of my research was on the concrete security of the Learning with Errors problem and its variants. My thesis investigates parameter selection in lattice-based cryptography.

University of Warwick

2009 - 2013

Mathematics (MMath, Hons)

I graduated with First Class Honours from an undergraduate Masters degree in mathematics. My MMath research project, in the area of Number Theory, was featured in the undergraduate prospectus!