Background and activities

Education Background

Royal Holloway University of LondonMSc in Mathematics of Cryptography.
University of KeeleBSc (Honours) in Mathematics.


My current research interests are broadly focused on the area of modern cryptocurrencies.

My most recent work within this area focuses on some of the major issues in the current Bitcoin implementation and relevant to all ‘blockchained’ cryptocurrencies. Our paper develops a framework, onto which cryptocurrencies can be built that we argue comes with some considerable advantages over the single chain models. We specifically target the issues of mining pools and transaction delays, and has the potential to offer considerable advantages over Blockchained constructions.

Blockchain-Free Cryptocurrencies. A Rational Framework for Truly Decentralised Fast Transactions. – under review. Co-authors: X. Boyen, T Haines

I also have a previous paper on the area of Client Puzzles and their potential within the Bitcoin, and the more general Blockchain framework.

Fair Client Puzzles from the Bitcoin Blockchain – ACISP 2016. Co-author: C. Boyd

I have some experience in Fully Homomorphic Encryption (FHE), where we looked at FHE and tried to formalise the early notions that emerged in this area, and present a clear, and holistic, guide for understanding FHE:

A Guide to Fully Homomorphic Encryption – The paper can be found on the eprint archive here, and is currently under review. Co-authors: F. Armknecht, C. Boyd, K. Gjøsteen, A. Jäschke, C. A. Reuter, M Strand

As well as interest in FHE, I have also worked on Identity Based Encryption (IBE), focusing on practical proposals for IBE in a multi-layered scenario under distinct private key generators (PKGs):

CARIBE: Adapting Traditional IBE for the Modern Key-Covetous Appetite. – Mycrypt 2016. Co-authors: D. Gligoroski and B. Hale

Master Level Projects

I am willing to consider project proposals in a variety of areas. If you have a suggestion you feel I would be interested in, please email me and we can discuss it. Alternatively, please take a look at the department website for suggested project work. 

Scientific, academic and artistic work

Displaying a selection of activities. See all publications in the database


  • Boyd, Colin Alexander; Boyen, Xavier; Carr, Christopher; Haines, Thomas. (2016) Key Recovery: Inert, Public, Transparent (KRIPT). Mycrypt 2016: Paradigm-shifting Crypto . MMU; Pullman Kuala Lumpur City Centre. 2016-12-01 - 2016-12-02.
  • Boyd, Colin Alexander; Carr, Christopher. (2016) Fair client puzzles from the Bitcoin blockchain. Lecture Notes in Computer Science. vol. 9722.
  • Hale, Britta J.; Carr, Christopher; Gligoroski, Danilo. (2016) CARIBE: Cascaded IBE for Maximum Flexibility and User-side Control. MyCrypt 2016: Paradigm-Shifting Crypto ; Kuala Lumpur, Malaysia. 2016-12-01 - 2016-12-02.


  • Hale, Britta; Carr, Christopher Alan; Gligoroski, Danilo. (2015) CARIBE-S: A Cascaded IBE Scheme for Maximum Flexibility and User-side Control. IFIP WG 11.4 Workshop – iNetSec 2015 . IBM Research – Zurich Lab; Zurich, Switzerland. 2015-10-29 - 2015-10-30.